समस्या निवारण और डिबगिंग लिनक्स प्रक्रियाओं के लिए 10 स्ट्रेस कमांड


स्ट्रेस यूनिक्स जैसे ऑपरेटिंग सिस्टम जैसे लिनक्स में डिबगिंग और परेशानी शूटिंग प्रोग्राम के लिए एक शक्तिशाली कमांड लाइन टूल है। यह एक प्रक्रिया द्वारा किए गए सभी सिस्टम कॉल और प्रक्रिया द्वारा प्राप्त संकेतों को कैप्चर और रिकॉर्ड करता है।

यह एक कोष्ठक में संलग्न अपने तर्कों और मानक त्रुटि पर इसके वापसी मूल्य के साथ प्रत्येक सिस्टम कॉल का नाम प्रदर्शित करता है; आप वैकल्पिक रूप से इसे फ़ाइल पर भी पुनर्निर्देशित कर सकते हैं।

इस लेख में, हम लिनक्स सिस्टम में समस्या निवारण और डिबगिंग कार्यक्रमों और प्रक्रियाओं के लिए 10 स्ट्रेस कमांड उदाहरणों की व्याख्या करेंगे।

लिनक्स में स्ट्रेस प्रोसेस मॉनिटरिंग टूल कैसे स्थापित करें

यदि स्ट्रेस आपके लिनक्स सिस्टम पर पूर्व-स्थापित नहीं है, तो इसे स्थापित करने के लिए, अपने वितरण के लिए नीचे उपयुक्त कमांड चलाएँ।

$ sudo apt install strace	#Debian/Ubuntu 
# yum install strace		#RHEL/CentOS
# dnf install strace		#Fedora 22+

यदि कोई प्रोग्राम दुर्घटनाग्रस्त हो जाता है या अपेक्षित तरीके से व्यवहार नहीं करता है, तो आप इसके निष्पादन के दौरान वास्तव में क्या हुआ, इसका सुराग पाने के लिए इसके सिस्टम कॉल के माध्यम से जा सकते हैं। जैसा कि हम बाद में देखेंगे, सिस्टम कॉल को विभिन्न घटनाओं के तहत वर्गीकृत किया जा सकता है: जो प्रक्रिया प्रबंधन से संबंधित हैं, जो एक फ़ाइल को एक तर्क के रूप में लेते हैं, जो नेटवर्किंग, मेमोरी मैपिंग, सिग्नल, आईपीसी शामिल करते हैं और विवरणक संबंधित सिस्टम कॉल भी दर्ज करते हैं।

आप निम्न उदाहरणों में -p विकल्प का उपयोग करके या तो स्ट्रीम के साथ एक प्रोग्राम/कमांड चला सकते हैं या उसमें एक PID पास कर सकते हैं।

1. ट्रेस लिनक्स कमांड सिस्टम कॉल

आप बस इस तरह से स्ट्रेस के साथ एक कमांड चला सकते हैं, यहां हम डीएफ कमांड द्वारा किए गए सभी सिस्टम कॉल का पता लगा रहे हैं।

$ strace df -h

execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "7ELF
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...

ऊपर दिए गए आउटपुट से, आप df कमांड द्वारा किए गए विभिन्न प्रकार के सिस्टम कॉल देख सकते हैं, उदाहरण के लिए।

open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3

कहा पे:

  • open – is the type of system call
  • (“/etc/ld.so.cache”, O_RDONLY|O_CLOEXEC) – system call argument
  • 3 – system call return value

नीचे एक सैंपल आउटपुट है जो लिखने के सिस्टम कॉल को दिखाता है, जो स्क्रीन पर df कमांड आउटपुट दिखाता है।

mmap(NULL, 26258, PROT_READ, MAP_SHARED, 3, 0) = 0x7f82f78f5000
close(3)                                = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
write(1, "Filesystem      Size  Used Avail"..., 49Filesystem      Size  Used Avail Use% Mounted on
) = 49
write(1, "udev            3.9G     0  3.9G"..., 43udev            3.9G     0  3.9G   0% /dev
) = 43
write(1, "tmpfs           788M  9.6M  779M"..., 43tmpfs           788M  9.6M  779M   2% /run
) = 43
write(1, "/dev/sda10      324G  252G   56G"..., 40/dev/sda10      324G  252G   56G  82% /
) = 40
write(1, "tmpfs           3.9G  104M  3.8G"..., 47tmpfs           3.9G  104M  3.8G   3% /dev/shm
) = 47
write(1, "tmpfs           5.0M  4.0K  5.0M"..., 48tmpfs           5.0M  4.0K  5.0M   1% /run/lock
) = 48
write(1, "tmpfs           3.9G     0  3.9G"..., 53tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
) = 53
write(1, "cgmfs           100K     0  100K"..., 56cgmfs           100K     0  100K   0% /run/cgmanager/fs
) = 56
write(1, "tmpfs           788M   36K  788M"..., 53tmpfs           788M   36K  788M   1% /run/user/1000
) = 53
close(1)                                = 0
close(2)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++

2. ट्रेस लिनक्स प्रक्रिया पीआईडी

यदि कोई प्रक्रिया पहले से चल रही है, तो आप इसे निम्न प्रकार से PID पास करके ट्रेस कर सकते हैं; यह आपकी स्क्रीन को आउटपुट जारी रखने के साथ भर देगा, जो प्रक्रिया द्वारा की जा रही सिस्टम कॉल दिखाता है, इसे समाप्त करने के लिए, [Ctrl + C] दबाएं।

$ sudo strace -p 3569

strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U0!70
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...

3. लिनक्स प्रक्रिया का सारांश प्राप्त करें

-c ध्वज का उपयोग करते हुए, आप प्रत्येक सिस्टम कॉल के लिए कुल समय, कॉल और त्रुटियों की रिपोर्ट बना सकते हैं, निम्नानुसार।

$ sudo strace -c -p 3569

strace: Process 3569 attached

^Cstrace: Process 3569 detached
% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 99.73    0.016000           8      1971           poll
  0.16    0.000025           0       509        75 futex
  0.06    0.000010           0      1985      1966 recvmsg
  0.06    0.000009           0      2336           mprotect
  0.00    0.000000           0       478           read
  0.00    0.000000           0        13           write
  0.00    0.000000           0        29           mmap
  0.00    0.000000           0         9           munmap
  0.00    0.000000           0        18           writev
  0.00    0.000000           0       351           madvise
  0.00    0.000000           0         1           restart_syscall
------ ----------- ----------- --------- --------- ----------------
100.00    0.016044                  7700      2041 total

4. सिस्टम कॉल के दौरान प्रिंट इंस्ट्रक्शन पॉइंटर

-i विकल्प प्रोग्राम द्वारा किए गए प्रत्येक सिस्टम कॉल के समय अनुदेश सूचक प्रदर्शित करता है।

$ sudo strace -i df -h

[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "7ELF
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...

5. प्रत्येक ट्रेस आउटपुट लाइन के लिए दिन का समय दिखाएं

आप ट्रेस आउटपुट में प्रत्येक पंक्ति के लिए दिन का समय प्रिंट कर सकते हैं, -t ध्वज को पास करके।

$ sudo strace -t df -h

15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "7ELF
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...

6. सिस्टम कॉल्स में प्रिंट कमांड टाइम स्पेंट

किसी प्रोग्राम द्वारा किए गए प्रत्येक सिस्टम कॉल की शुरुआत और समाप्ति के बीच के समय के अंतर को दिखाने के लिए, -T विकल्प का उपयोग करें।

$ sudo strace -T df -h

execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0 <0.000287>
brk(NULL)                               = 0xeca000 <0.000035>
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory) <0.000028>
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9aff2b1000 <0.000020>
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory) <0.000019>
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3 <0.000022>
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0 <0.000015>
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f9aff28c000 <0.000019>
close(3)                                = 0 <0.000014>
...

7. ट्रेस केवल विशिष्ट प्रणाली कॉल

नीचे दिए गए आदेश में, ट्रेस = लिखना एक योग्यता अभिव्यक्ति के रूप में जाना जाता है, जहां ट्रेस एक क्वालीफायर है (अन्य में सिग्नल, एब्बर, वर्बोज़, रॉ, रीड, या राइट शामिल हैं) । यहां, लिखना क्वालीफायर का मूल्य है।

निम्न कमांड वास्तव में मानक आउटपुट पर df आउटपुट प्रिंट करने के लिए सिस्टम कॉल दिखाता है।

$ sudo strace -e trace=write df -h

write(1, "Filesystem      Size  Used Avail"..., 49Filesystem      Size  Used Avail Use% Mounted on
) = 49
write(1, "udev            3.9G     0  3.9G"..., 43udev            3.9G     0  3.9G   0% /dev
) = 43
write(1, "tmpfs           788M  9.6M  779M"..., 43tmpfs           788M  9.6M  779M   2% /run
) = 43
write(1, "/dev/sda10      324G  252G   56G"..., 40/dev/sda10      324G  252G   56G  82% /
) = 40
write(1, "tmpfs           3.9G  104M  3.8G"..., 47tmpfs           3.9G  104M  3.8G   3% /dev/shm
) = 47
write(1, "tmpfs           5.0M  4.0K  5.0M"..., 48tmpfs           5.0M  4.0K  5.0M   1% /run/lock
) = 48
write(1, "tmpfs           3.9G     0  3.9G"..., 53tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
) = 53
write(1, "cgmfs           100K     0  100K"..., 56cgmfs           100K     0  100K   0% /run/cgmanager/fs
) = 56
write(1, "tmpfs           788M   28K  788M"..., 53tmpfs           788M   28K  788M   1% /run/user/1000
) = 53
+++ exited with 0 +++

ट्रेस क्वालीफायर के बारे में कुछ अतिरिक्त कमांड इस प्रकार हैं।

$ sudo strace -e trace=open,close df -h
$ sudo strace -e trace=open,close,read,write df -h
$ sudo strace -e trace=all df -h	

8. एक निश्चित स्थिति के आधार पर ट्रेस सिस्टम कॉल

आइए देखें कि किसी दिए गए वर्ग की घटनाओं से संबंधित सिस्टम कॉल का पता कैसे लगाया जाए। इस आदेश का उपयोग प्रक्रिया प्रबंधन से संबंधित सभी सिस्टम कॉल का पता लगाने के लिए किया जा सकता है।

$ sudo strace -q -e trace=process df -h	

execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
arch_prctl(ARCH_SET_FS, 0x7fe2222ff700) = 0
Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           788M  9.6M  779M   2% /run
/dev/sda10      324G  252G   56G  82% /
tmpfs           3.9G  104M  3.8G   3% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           788M   28K  788M   1% /run/user/1000
exit_group(0)                           = ?
+++ exited with 0 +++

अगला, एक तर्क के रूप में फ़ाइल नाम लेने वाले सभी सिस्टम कॉल का पता लगाने के लिए, इस कमांड को चलाएं।

$ sudo strace -q  -e trace=file df -h

execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
open("/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3
...

मेमोरी मैपिंग से जुड़े सभी सिस्टम कॉल को ट्रेस करने के लिए टाइप करें।

$ sudo strace -q -e trace=memory df -h	

brk(NULL)                               = 0x77a000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4658000
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe8f4633000
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe8f406b000
mprotect(0x7fe8f422b000, 2097152, PROT_NONE) = 0
mmap(0x7fe8f442b000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c0000) = 0x7fe8f442b000
mmap(0x7fe8f4431000, 14752, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4431000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4632000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4631000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4630000
mprotect(0x7fe8f442b000, 16384, PROT_READ) = 0
mprotect(0x616000, 4096, PROT_READ)     = 0
mprotect(0x7fe8f465a000, 4096, PROT_READ) = 0
munmap(0x7fe8f4633000, 147662)          = 0
mmap(NULL, 2981280, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe8f3d93000
brk(NULL)                               = 0x77a000
brk(0x79b000)                           = 0x79b000
mmap(NULL, 619, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe8f4657000
mmap(NULL, 26258, PROT_READ, MAP_SHARED, 3, 0) = 0x7fe8f4650000
Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           788M  9.6M  779M   2% /run
/dev/sda10      324G  252G   56G  82% /
tmpfs           3.9G  104M  3.8G   3% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           788M   28K  788M   1% /run/user/1000
+++ exited with 0 +++

आप सभी नेटवर्क और सिग्नल संबंधित सिस्टम कॉल को ट्रेस कर सकते हैं।

$ sudo strace -e trace=network df -h
$ sudo strace -e trace=signal df -h

9. रीडायरेक्ट ट्रेस आउटपुट फाइल में

मानक त्रुटि के लिए भेजे गए ट्रेस संदेशों को फ़ाइल में लिखने के लिए, -o विकल्प का उपयोग करें। इसका मतलब है कि स्क्रीन पर केवल कमांड आउटपुट प्रिंट किया गया है जैसा कि नीचे दिखाया गया है।

$ sudo strace -o df_debug.txt df -h

Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           788M  9.6M  779M   2% /run
/dev/sda10      324G  252G   56G  82% /
tmpfs           3.9G  104M  3.8G   3% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           788M   28K  788M   1% /run/user/1000

फ़ाइल के माध्यम से देखने के लिए, कैट कमांड का उपयोग करें।

$ cat df_debug.txt 

10. स्ट्रेस के कुछ डिबगिंग आउटपुट दिखाएं

स्ट्रेस टूल के लिए डिबगिंग जानकारी दिखाने के लिए, -d ध्वज का उपयोग करें।

$ strace -d df -h

अतिरिक्त जानकारी के लिए, स्ट्रेस मैन पेज देखें।

$ man strace

इन उपयोगी संबंधित लेखों को भी पढ़ें:

  1. 20 Command Line Tools to Monitor Linux Performance
  2. Sysdig – A Powerful System Monitoring and Troubleshooting Tool for Linux
  3. How to Trace Execution of Commands in Shell Script with Shell Tracing
  4. BCC – Dynamic Tracing Tools for Linux Performance Monitoring, Networking and More

अंत में, स्ट्रेस प्रोग्राम विफलता का कारण (ओं) के निदान के लिए एक उल्लेखनीय उपकरण है: यह एक शक्तिशाली डिबगिंग और परेशानी शूटिंग है। यह अनुभवी सिस्टम प्रशासक, प्रोग्रामर और हैकर्स के लिए व्यावहारिक रूप से उपयोगी है। इस लेख से संबंधित किसी भी विचार को साझा करने के लिए, नीचे दिए गए फीडबैक फॉर्म का उपयोग करें।