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Commands tagged test from sorted by
Terminal - Commands tagged test - 14 results
echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE
2015-05-09 14:58:41
User: pung96
Functions: echo perl

perl version of "Wait for file to stop changing"

When "FileName" has not been changed for last 10 seconds, then print "DONE"

"10" in "(stat)[10]" means ctime.

One have other options like atime, mtime and others. http://perldoc.perl.org/functions/stat.html

while [ $(( $(date +%s) - $(stat -c %Y FILENAME) )) -lt 10 ]; do sleep 1; done; echo DONE
2015-05-09 12:30:13
User: flatcap
Functions: date echo sleep stat

This loop will finish if a file hasn't changed in the last 10 seconds.


It checks the file's modification timestamp against the clock.

If 10 seconds have elapsed without any change to the file, then the loop ends.


This script will give a false positive if there's a 10 second delay between updates,

e.g. due to network congestion


How does it work?

'date +%s' gives the current time in seconds

'stat -c %Y' gives the file's last modification time in seconds

'$(( ))' is bash's way of doing maths

'[ X -lt 10 ]' tests the result is Less Than 10

otherwise sleep for 1 second and repeat


Note: Clever as this script is, inotify is smarter.

for i in `cat hosts_list`; do RES=`ssh myusername@${i} "ps -ef " |awk '/[p]rocessname/ {print $2}'`; test "x${RES}" = "x" && echo $i; done
2014-10-03 14:57:54
User: arlequin
Functions: awk echo test
Tags: ssh awk test ps

Given a hosts list, ssh one by one and echo its name only if 'processname' is not running.

rm -v *.(log|toc|aux|nav|snm|out|tex.backup|bbl|blg|bib.backup|vrb|lof|lot|hd|idx)(.e/'[[ -f ${REPLY:r}.tex ]]'/)
2012-09-18 20:49:28
User: xro
Functions: rm
Tags: rm zsh latex test

Uses zsh globbing syntax to safely remove all the files known to be generated by LaTeX, but only if there is actually a .tex source file with the same basename present. So we don't accidentally delete a .nav .log or .out file that has nothing to do with LaTeX, e/'[[ -f ${REPLY:r}.tex ]]'/ actually checks for the existance of a .tex file of the same name, beforehand.

A different way to do this, would be to glob all *.tex files and generate a globbing pattern from them:

TEXTEMPFILES=(*.tex(.N:s/%tex/'(log|toc|aux|nav|snm|out|tex.backup|bbl|blg|bib.backup|vrb|lof|lot|hd|idx)(.N)'/)) ; rm -v ${~TEXTEMPFILES}

or, you could use purge() from grml-etc-core ( http://github.com/grml/grml-etc-core/blob/master/usr_share_grml/zsh/functions/purge )

testt(){ o=abcdefghLkprsStuwxOGN;echo $@;for((i=0;i<${#o};i++));do c=${o:$i:1};test -$c $1 && help test | sed "/^ *-$c/!d;1q;s/^[^T]*/-$c /;s/ if/ -/";done; }
2012-02-21 16:54:53
User: AskApache
Functions: echo sed test

Applies each file operator using the built-in test.

testt /home/askapache/.sq


-a True - file exists.

-d True - file is a directory.

-e True - file exists.

-r True - file is readable by you.

-s True - file exists and is not empty.

-w True - the file is writable by you.

-x True - the file is executable by you.

-O True - the file is effectively owned by you.

-G True - the file is effectively owned by your group.

-N True - the file has been modified since it was last read.

Full Function:

testt ()


local dp;

until [ -z "${1:-}" ]; do


[[ ! -a "$1" ]] && dp="$PWD/$dp";

command ls -w $((${COLUMNS:-80}-20)) -lA --color=tty -d "$dp";

[[ -d "$dp" ]] && find "$dp" -mount -depth -wholename "$dp" -printf '%.5m %10M %#15s %#9u %-9g %#5U %-5G %Am/%Ad/%AY %Cm/%Cd/%CY %Tm/%Td/%TY [%Y] %p\n' -a -quit 2> /dev/null;

for f in a b c d e f g h L k p r s S t u w x O G N;


test -$f "$dp" && help test | sed "/-$f F/!d" | sed -e 's#^[\t ]*-\([a-zA-Z]\{1\}\) F[A-Z]*[\t ]* True if#-\1 "'$dp'" #g';





cd() { if [ -n "$1" ]; then [ -f "$1" ] && set -- "${1%/*}"; else [ -n "$CDDIR" ] && set -- "$CDDIR"; fi; command cd "$@"; }
2011-06-24 08:48:13
User: flatcap
Functions: cd command set
Tags: cd test set

Move efficiently between directories.


This command adds a couple of extra features to cd, without affecting normal use.

CDPATH use is also unaffected. It introduces and environment variable CDDIR which is used as an alternate home directory.


Note: I don't want to alter $HOME because then all my dot files will move.




cd dir

Change directory to "dir" (using CDPATH if necessary)


cd dir/file.txt

Change directory to "dir" (containing folder of "file.txt")

This allows you to cut'n'paste, or use


CDDIR is unset


Change directory to $HOME




Change directory to /home/flatcap/work


For convenience, put the command, and the following, in your .bashrc or .bash_profile

export CDDIR="/home/flatcap/work"

alias cdd="CDDIR=$(pwd)"

taskset 0x00000001 yes > /dev/null &
2011-04-03 07:23:53
User: kerim
Functions: taskset yes

For each cpu set mask and then monitor your cpu infos. Temp,load avg. etc.

For example for 2nd cpu or 2nd core

taskset 0x00000002 yes > /dev/null &

For example for 3rd cpu or 3rd core

taskset 0x00000004 yes > /dev/null &

For example for 4th cpu or 4th core

taskset 0x00000008 yes > /dev/null &

Monitor your cpu temp with this command if you want

watch -n1 "acpi -t"

Load avg. from top command




iperf -s
2011-01-24 07:58:38
User: forcefsck

On the machine acting like a server, run:

iperf -s

On the machine acting like a client, run:

iperf -c ip.add.re.ss

where ip.add.re.ss is the ip or hostname of the server.

nc -l -p 7777 > /dev/null
2011-01-24 00:06:45
User: kerim

On the another machine write this command.

pv -r /dev/zero | nc 7777

It will show live throughput between two machine.The destination machine ip is at our example

You must multiply by 8 for the network calculation.

You must install pv and netcat commands for this commands usage.



leapyear() { [ $(date -d "Dec 31, $1" +%j) == 366 ] && echo leap || echo not leap; }
leapyear() { if [ $[$1 % 4] -eq 0 ] && [ $[$1 % 100] -ne 0 ] || [ $[$1 % 400] -eq 0 ]; then echo $1' is a leap year!'; else echo $1' is not a leap year.'; fi; }
2010-03-30 17:19:20
User: kaedenn
Functions: echo
Tags: echo test

Tested on bash, and follows all the rules about leap years.

for p in ${PATH//:/ }; do [[ -d $p && -x $p ]] && echo $p; done
2009-09-19 06:43:57
User: AskApache
Functions: echo

Finds executable and existing directories in your path that can be useful if migrating a profile script to another system. This is faster and smaller than any other method due to using only bash builtin commands.

See also:

+ http://www.commandlinefu.com/commands/view/743/list-all-execs-in-path-usefull-for-grepping-the-resulting-list

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

perl -e '$p=qr!(?:0|1\d{0,2}|2(?:[0-4]\d?|5[0-5]?|[6-9])?|[3-9]\d?)!;print((shift=~m/^$p\.$p\.$p\.$p$/)?1:0);'
2009-07-12 00:24:29
User: speaker
Functions: perl

This command will output 1 if the given argument is a valid ip address and 0 if it is not.