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Commands tagged strace

Terminal - Commands tagged strace - 12 results

dtruss [ -p <pid> | -n <pname> ]

2013-02-22 11:09:55

User: Zulu

Tags: strace dtruss

-1

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strace alternative for Mac OS X

Usefull tool for debug process.

ps h --ppid $(cat /var/run/apache2.pid) | awk '{print"-p " $1}' | xargs sudo strace

2012-03-21 01:59:41

User: colinmollenhour

Functions: awk cat ps sudo xargs

Tags: awk apache ps strace

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easily strace all your apache *child* processes

Like the original version except it does not include the parent apache process or the grep process and adds "sudo" so it can be run by user.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

stap -v strace.stp -c /path/to/command

2011-10-07 08:27:57

User: gerard

Tags: strace systemtap

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strace like SystemTap script

The stap script is :

#! /usr/bin/env stap

probe syscall.* {

if (pid() == target())

printf("%s %s\n", name, argstr);

}

strace -ff -e trace=file my_command 2>&1 | perl -ne 's/^[^"]+"(([^\\"]|\\[\\"nt])*)".*/$1/ && print'

2011-08-16 15:00:18

User: unixmonkey8046

Functions: perl strace

Tags: file monitoring strace

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List files accessed by a command

Can be run as a script `ftrace` if my_command is substrituted with "$@"

It is useful when running a command that fails and you have the feeling it is accessing a file you are not aware of.

pidof httpd | sed 's/ / -p /g' | xargs strace -fp

2011-06-28 09:53:19

User: daniele

Functions: pidof sed strace xargs

Tags: debug apache strace

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See what apache is doing without restarting it in debug mode

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ps -C apache o pid= | sed 's/^/-p /' | xargs strace

2011-03-15 08:46:33

User: depesz

Functions: ps sed xargs

Tags: awk token ps strace tokenizer

-1

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easily strace all your apache processes

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strace -e write=1,2 -p $PID 2>&1 | sed -un "/^ |/p" | sed -ue "s/^.\{9\}$.\{50\}$.\+/\1/g" -e 's/ //g' | xxd -r -p

2010-10-06 19:37:39

User: glaudiston

Functions: sed strace

Tags: output stdout strace stderr

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intercept stdout/stderr of another process or disowned process

Useful to recover a output(stdout and stderr) "disown"ed or "nohup"ep process of other instance of ssh.

With the others options the stdout / stderr is intercepted, but only the first n chars.

This way we can recover ALL text of stdout or stderr

2010-04-23 16:22:17

User: systemj

Functions: cut grep sed strace

Tags: output stdout strace stderr

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intercept stdout/stderr of another process

similar to the previous command, but with more friendly output (tested on linux)

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strace php tias.php -e open,access 2>&1 | grep foo.txt

2010-04-20 19:42:42

User: rkulla

Functions: grep strace

Tags: permissions debug strace errors

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See why a program can't seem to access a file

Sometimes a program refuses to read a file and you're not sure why. You may have display_errors turned off for PHP or something. In this example, fopen('/var/www/test/foo.txt') was called but doesn't have read access to foo.txt.

Strace can tell you what went wrong. E.g., if php doesn't have read access to the file, strace will say "EACCESS (Permission denied)". Or, if the file path you gave doesn't exist, strace will say "ENOENT (No such file or directory)", etc.

This works for any program you can run from the command-line, e.g., strace python myapp.py -e open,access...

Note: the above command uses php-cli, not mod_php, which is a different SAPI with diff configs, etc.

strace -ff -e trace=write -e write=1,2 -p SOME_PID

2010-04-20 08:55:54

User: oernii2

Functions: strace

Tags: output stdout strace stderr

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intercept stdout/stderr of another process

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termtrace(){( strace -s 1000 -e write tput $@ 2>&2 2>&1 ) | grep -o '"[^"]*"';}

This is sample output - yours may be different.

$ for cap in `infocmp -1q|sed 's/ *//g'|grep -v '#\||' |cut -d= -f1|tr "\n" ' '`; do echo "$cap: `termtrace $cap 5`"; done
bel: "\7"
blink: "\33[5m"
bold: "\33[1m"
cbt: "\33[Z"
civis: "\33[?25l"
clear: "\33[H\33[2J"
cnorm: "\33[?12l\33[?25h"
cr: "\r"
csr: "\33[6;1r"
cub: "\33[5D"
cub1: "\10"
cud: "\33[5B"
cud1: "\n"
cuf: "\33[5C"
cuf1: "\33[C"
cup: "\33[6;1H"
cuu: "\33[5A"
cuu1: "\33[A"
cvvis: "\33[?12;25h"
dch: "\33[5P"
dch1: "\33[P"
dl: "\33[5M"
dl1: "\33[M"
ech: "\33[5X"
ed: "\33[J"
el: "\33[K"
el1: "\33[1K"
flash: "\33[?5h"
"\33[?5l"
home: "\33[H"
hpa: "\33[6G"
ht: "\t"
hts: "\33H"
ich: "\33[5@"
il: "\33[5L"
il1: "\33[L"
ind: "\n"
indn: "\33[5S"
initc: "\33]4;5;rgb:00/00/00\33\\"
invis: "\33[8m"
is2: "\33[!p\33[?3;4l\33[4l\33>"
kDC: "\33[3;2~"
kEND: "\33[1;2F"
kHOM: "\33[1;2H"
kIC: "\33[2;2~"
kLFT: "\33[1;2D"
kNXT: "\33[6;2~"
kPRV: "\33[5;2~"
kRIT: "\33[1;2C"
kb2: "\33OE"
kbs: "\177"
kcbt: "\33[Z"
kcub1: "\33OD"
kcud1: "\33OB"
kcuf1: "\33OC"
kcuu1: "\33OA"
kdch1: "\33[3~"
kend: "\33OF"
kent: "\33OM"
kf1: "\33OP"
kf10: "\33[21~"
kf11: "\33[23~"
kf12: "\33[24~"
kf13: "\33O2P"
kf14: "\33O2Q"
kf15: "\33O2R"
kf16: "\33O2S"
kf17: "\33[15;2~"
kf18: "\33[17;2~"
kf19: "\33[18;2~"
kf2: "\33OQ"
kf20: "\33[19;2~"
kf21: "\33[20;2~"
kf22: "\33[21;2~"
kf23: "\33[23;2~"
kf24: "\33[24;2~"
kf25: "\33O5P"
kf26: "\33O5Q"
kf27: "\33O5R"
kf28: "\33O5S"
kf29: "\33[15;5~"
kf3: "\33OR"
kf30: "\33[17;5~"
kf31: "\33[18;5~"
kf32: "\33[19;5~"
kf33: "\33[20;5~"
kf34: "\33[21;5~"
kf35: "\33[23;5~"
kf36: "\33[24;5~"
kf37: "\33O6P"
kf38: "\33O6Q"
kf39: "\33O6R"
kf4: "\33OS"
kf40: "\33O6S"
kf41: "\33[15;6~"
kf42: "\33[17;6~"
kf43: "\33[18;6~"
kf44: "\33[19;6~"
kf45: "\33[20;6~"
kf46: "\33[21;6~"
kf47: "\33[23;6~"
kf48: "\33[24;6~"
kf49: "\33O3P"
kf5: "\33[15~"
kf50: "\33O3Q"
kf51: "\33O3R"
kf52: "\33O3S"
kf53: "\33[15;3~"
kf54: "\33[17;3~"
kf55: "\33[18;3~"
kf56: "\33[19;3~"
kf57: "\33[20;3~"
kf58: "\33[21;3~"
kf59: "\33[23;3~"
kf6: "\33[17~"
kf60: "\33[24;3~"
kf61: "\33O4P"
kf62: "\33O4Q"
kf63: "\33O4R"
kf7: "\33[18~"
kf8: "\33[19~"
kf9: "\33[20~"
khome: "\33OH"
kich1: "\33[2~"
kind: "\33[1;2B"
kmous: "\33[M"
knp: "\33[6~"
kpp: "\33[5~"
kri: "\33[1;2A"
mc0: "\33[i"
mc4: "\33[4i"
mc5: "\33[5i"
meml: "\33l"
memu: "\33m"
op: "\33[39;49m"
rc: "\0338"
rev: "\33[7m"
ri: "\33M"
rin: "\33[5T"
rmacs: "\33(B"
rmam: "\33[?7l"
rmcup: "\33[?1049l"
rmir: "\33[4l"
rmkx: "\33[?1l\33>"
rmso: "\33[27m"
rmul: "\33[24m"
rs1: "\33c"
rs2: "\33[!p\33[?3;4l\33[4l\33>"
sc: "\0337"
setab: "\33[45m"
setaf: "\33[35m"
sgr0: "\33(B\33[m"
smacs: "\33(0"
smam: "\33[?7h"
smcup: "\33[?1049h"
smir: "\33[4h"
smkx: "\33[?1h\33="
smso: "\33[7m"
smul: "\33[4m"
tbc: "\33[3g"
u6: "\33[5;0R"
u7: "\33[6n"
u8: "\33[?1;2c"
u9: "\33[c"
vpa: "\33[6d"

2010-03-17 08:53:41

User: AskApache

Functions: grep strace tput write

Tags: color tput askapache escape reset terminfo termcap term strace

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Terminal Escape Code Zen - Strace and Tput

Depending on the TERM, the terminfo version, ncurses version, etc.. you may be using a varied assortment of terminal escape codes. With this command you can easily find out exactly what is going on.. This is terminal escape zen!

( 2>&2 strace -f -F -e write -s 1000 sh -c 'echo -e "initc\nis2\ncnorm\nrmso\nsgr0" | tput -S' 2>&1 ) | grep -o '"\\[^"]*"' --color=always

"\33]4;%p1%d;rgb:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\33\\\33[!p\33[?3;4l\33[4l\33>\33[?12l\33[?25h\33[27m\33(B\33[m"

Lets say you want to find out what you need to echo in order to get the text to blink..

echo -e "`tput blink`This will blink`tput sgr0` This wont"

Now you can use this function instead of calling tput (tput is much smarter for portable code because it works differently depending on the current TERM, and tput -T anyterm works too.) to turn that echo into a much faster executing code. tput queries files, opens files, etc.. but echo is very strait and narrow.

So now you can do this:

echo -e "\33[5mThis will blink\33(B\33[m This wont"

More at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

straceprocessname(){ x=( $(pgrep "$@") ); [[ ${x[@]} ]] || return 1; strace -vf ${x[@]/#/-p }; }

2009-12-03 00:04:39

User: sputnick

Functions: return strace

Tags: strace sysadmin

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Strace all signals processes based on a name ( The processes already started... ) with bash built-in

Especially for sysadmins when they don't want to waste time to add -p flag on the N processes of a processname.

In the old school, you did ;

pgrep processname

and typing strace -f -p 456 -p 678 -p 974...

You can add -f argument to the function. That way, the function will deal with pgrep to match the command-line.

Example :

processname -f jrockit

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