Commands using exit sorted by votes

Commands using exit (19)

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Make sure a script is run in a terminal.

Exit with error if script is not run in a terminal
This is sample output - yours may be different.
21

[ -t 0 ] || exit 1

cfajohnson · 2009-11-20 23:14:49 13
Cleanly manage tempfiles in scripts

Cleanly create tempfiles using mktemp and remove them using traps instead of removing them in the end of the script. This way, you make sure the tempfiles are removed properly even if the script is killed or interrupted. For a user script in KDE4, you can set TMPROOT using : TMPROOT=$(kde4-config --path tmp)
This is sample output - yours may be different.
3

TMPROOT=/tmp; TMPDIR=$(mktemp -d $TMPROOT/somedir.XXXXXX); TMPFILE=$(mktemp $TMPROOT/somefile.XXXXXX); trap "rm -rf $TMPDIR $TMPFILE; exit" INT TERM EXIT; some treatment using $TMPDIR and $TMPFILE; exit 0

raphink · 2009-02-24 09:35:22 6
Pronounce an English word using Merriam-Webster.com

Looks up a word on merriam-webster.com, does a screen scrape for the FIRST audio pronunciation and plays it. USAGE: Put this one-liner into a shell script (e.g., ~/bin/pronounce) and run it from the command line giving it the word to say: pronounce lek If the word isn't found in merriam-webster, no audio is played and the script returns an error value. However, M-W is a fairly complete dictionary (better than howjsay.com which won't let you hear how to pronounce naughty words). ASSUMPTIONS: GNU's sed (which supports -r for extended regular expressions) and Linux's aplay. Aplay can be replaced by any program that can play .WAV files from stdin. KNOWN BUGS: only the FIRST pronunciation is played, which is problematic if you wanted a particular form (plural, adjectival, etc) of the word. For example, if you run this: pronounce onomatopoetic you'll hear a voice saying "onomatopoeia". Playing the correct form of the word is possible, but doing so might make the screen scraper even more fragile than it already is. (The slightest change to the format of m-w.com could break it). Show Sample Output
This is sample output - yours may be different.
```
$ pronounce bodhisattva
[ You hear a voice ]
$ pronounce asdfasdfasdf || echo "Sorry, I can't say that."
Sorry, I can't say that.
```
3

cmd=$(wget -qO- "http://www.m-w.com/dictionary/$(echo "$@"|tr '[A-Z]' '[a-z]')" | sed -rn "s#return au$'([^']+?)', '([^'])[^']*'$;.*#\nwget -qO- http://cougar.eb.com/soundc11/\2/\1 | aplay -q#; s/[^\n]*\n//p"); [ "$cmd" ] && eval "$cmd" || exit 1

hackerb9 · 2010-03-12 13:56:41 4
Batch edition of all OpenOffice.org Writer files in the current directory (body text)

This function does a batch edition of all OOO3 Writer files in current directory. It uses sed to search a FOO pattern into body text of each file, then replace it to foo pattern (only the first match) . I did it because I've some hundreds of OOO3 Writer files where I did need to edit one word in each ones and open up each file in OOO3 gui wasn't an option. Usage: bsro3 FOO foo
This is sample output - yours may be different.
2

bsro3 () { P=`pwd`; S=$1; R=$2; ls *.odt > /dev/null 2>&1; if [[ $? -ne 0 ]]; then exit 1; fi; for i in *.odt; do mkdir ${P}/T; cd ${P}/T; unzip -qq "$P"/"$i"; sed -i "s/$S/$R/" ${P}/T/content.xml; zip -qq -r "$P"/"$i" *; cd ${P}; rm -rf ${P}/T; done; }

danpos · 2010-06-30 04:43:54 8
MSDOS command to check existance of command and exit batch if failed

This is a command to be used inside of MS-DOS batch files to check existence of commands as preconditions before actual batch processing can be started. If the command is found, batch script continues execution. If not, a message is printed on screen, script then waits for user pressing a key and exits. An error message of the command itself is suppressed for clarity purpose. Show Sample Output
This is sample output - yours may be different.
```
bash --version >NUL 2>&1 || ( echo Bash not found. Please install cygwin or check PATH variable! & pause & exit )

Bash not found. Please install cygwin or check PATH variable!
Press any key to continue . . .
```
2

<command> >NUL 2>&1 || ( echo <Command> not found. Please install <command> or check PATH variable! & pause & exit )

Marco · 2011-03-07 14:27:42 8
Check variable has been set
This is sample output - yours may be different.
1

[ -z "$VAR" ] && echo "VAR has not been set" && exit 1

sharfah · 2009-09-14 17:03:16 4
validate xml in a shell script using xmllint
This is sample output - yours may be different.
1

xmllint --noout some.xml 2>&1 >/dev/null || exit 1

putnamhill · 2009-12-11 16:36:21 7
Check if the Debian package was used since its installation/upgrade.

This script compares the modification date of /var/lib/dpkg/info/${package}.list and all the files mentioned there. It could be wrong on noatime partitions. Here is non-oneliner: #!/bin/sh package=$1; list=/var/lib/dpkg/info/${package}.list; inst=$(stat "$list" -c %X); cat $list | ( while read file; do if [ -f "$file" ]; then acc=$(stat "$file" -c %X); if [ $inst -lt $acc ]; then echo used $file exit 0 fi; fi; done exit 1 ) Show Sample Output
This is sample output - yours may be different.
```
vadim@gaendalf:~$ wasused mc
used /usr/bin/mcedit
vadim@gaendalf:~$ wasused netbeans-platform
vadim@gaendalf:~$ echo $?
1
vadim@gaendalf:~$
```
1

package=$1; list=/var/lib/dpkg/info/${package}.list; inst=$(stat "$list" -c %X); cat $list | (while read file; do if [ -f "$file" ];then acc=$(stat "$file" -c %X); if [ $inst -lt $acc ]; then echo used $file; exit 0; fi; fi; done; exit 1)

pipeliner · 2010-09-20 18:10:19 6
Make sure your script runs with a minimum Bash version

If you use new features of a certain Bash version in your shell script, make sure that it actually runs with the required version.
This is sample output - yours may be different.
1

if [ -z "${BASH_VERSINFO}" ] || [ -z "${BASH_VERSINFO[0]}" ] || [ ${BASH_VERSINFO[0]} -lt 4 ]; then echo "This script requires Bash version >= 4"; exit 1; fi

hfs · 2011-02-25 11:02:47 6
extracts 64 bytes of random digits from random lines out of /dev/random sent to stdio

Use this the next time you need to come up with a reasonably random bitstring, like for a WPA/WPA2 PSK or something. Takes a continuous stream of bytes coming from /dev/urandom, runs it through od(1), picking a random field ($0 and $1 excluded) from a random line and then prints it. Show Sample Output
This is sample output - yours may be different.
```
afca515ee00c0c92637ee8d7a476f8a380b969cc43e205bb086e622f2b77ebdd
```
1

cat /dev/urandom|od -t x1|awk 'NR > line { pos=int(rand()*15)+2;printf("%s",$pos);line=NR+(rand()*1000);digits = digits+2 } digits == 64 { print("\n");exit }'

jetdillo · 2012-08-14 19:02:00 7
Make sure a script is run in a terminal.

If your script needs to be run in a terminal, this line at the top will stop it running if you absent-mindedly double-click the icon, perhaps intending to edit it. (Of course this won't help with scripts that run in the background.)
This is sample output - yours may be different.
0

tty > /dev/null 2>&1 || { aplay error.wav ; exit 1 ;}

johnraff · 2009-11-04 16:18:00 6
Check if commands are available on your system
This is sample output - yours may be different.
0

for c in gcc bison dialog bc asdf; do if ! which $c >/dev/null; then echo Required program $c is missing ; exit 1; fi; done

Mozai · 2011-06-27 12:54:02 4
Basic Shell function die_msg

Using a standard way to handle error message and return code. Show Sample Output
This is sample output - yours may be different.
```
cd /path/to/somewhere || die_msg Cannot change CWD to somewhere
```
0

die_msg() { echo $@ >&2; exit -1; }

admon · 2012-02-24 04:06:04 4
grep in .odt files

find '.odt' files that contain USAGE: grepodt
This is sample output - yours may be different.
0

grepodt () { W=$1;P=$2;ls *.odt > /dev/null 2>&1;if [[ $? -ne 0 ]];then exit 1;fi;if [[ ! "$P" ]];then P='*';fi;for i in $P.odt;do unzip -qq "$i" content.xml;grep -l $W content.xml>/dev/null;if [[ $? -eq 0 ]];then echo $i;fi;rm content.xml; done;}

roberto_scotti · 2015-12-09 20:37:52 10
Get just LAN IP without all the extra stuff

I just needed to store the LAN IP (for ipv4) in a variable for a specific task in a bash script. I figured I'd share. I sent it to a variable with VAR=$(stuff) and used it later on. I put the exit 0 in the if statement to make it so that it breaks if there are more than one IPv4 addresses assigned. I only wanted the first one. Edit: Bear in mind, my network mask is a double digit number so if you have a smaller nw mask you'd need to edit the sed statement. Show Sample Output
This is sample output - yours may be different.
```
192.168.1.245
```
0

ip addr show | grep "inet " | while read INET IP TRASH; do if [ $IP != "127.0.0.1/8" ]; then echo $IP; exit 0; fi; done | sed s:/[1-9][1-9]:"":

Meh · 2016-04-07 17:46:20 11
Get only headers from a website with curl even if it doesn't support HEAD

Some sites running on basic web servers don't support the HEAD request, so using "curl -I" on them doesn't work. This will automatically try "curl -I" at first and if that fails with a 4xx or 5xx status code, it falls back to "curl -i" and prints only the headers from that.
This is sample output - yours may be different.
0

curlh() { x="$(curl -Is -w '%{http_code}' "$@")"; if [[ "$(tail -n 1 <<< "$x")" == [45]* ]]; then curl -is "$@" | awk '{ if (!NF) { exit }; print }'; else head -n -1 <<< "$x"; fi; }

nyuszika7h · 2017-07-10 12:29:00 17
validate xml in a shell script.

For debian likes, that's in python-xml package.
This is sample output - yours may be different.
-1

xmlproc_parse.python-xml &>/dev/null <FILE> || exit 1

sputnick · 2009-12-11 17:30:03 6
Find out if a module is installed in perl

Will check if the given module is installed in the @INC. It will print the path and return 0 if found, or 1 otherwise. Based on script from SharpyWarpy in http://www.linuxquestions.org/questions/linux-general-1/how-to-list-all-installed-perl-modules-216603/ Show Sample Output
This is sample output - yours may be different.
```
/usr/local/share/perl5/Collectd/Plugins/Graphite.pm
```
-1

perl -MFile::Find=find -MFile::Spec::Functions -Tlwe '$found=1; find { wanted => sub { if (/$ARGV[0]\.pm\z/) { print canonpath $_; $found=0; } }, no_chdir => 1 }, @INC; exit $found;' Collectd/Plugins/Graphite

keymon · 2013-01-11 11:01:46 6
Remove "ssh host" from known hosts file.

I have this as a file called deletekey in my ~/bin. Makes life a little easier.
This is sample output - yours may be different.
-13

echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi

DaveQB · 2010-07-11 23:09:11 5

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Grep Recursively Through Single File Extension

Trac 0.12.2-stable

To get the CPU temperature continuously on the desktop

There is no need for variables. I also added sleep to reduce cpu usage, however I didn't test it.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

dump 1KB of data from ram to file

about how using internal separate field and store file content on variable

download newest adminer and rename to it's version accordingly

If the version already downloaded. it will not download again

Show permissions of current directory and all directories upwards to /

NB not 'namei -m .', as it slices the path you give it.

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Benchmark SQL Query

Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

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Commands using exit (19)

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