Commands using perl (369)
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Start an interactive program with perl code expansion. Everything between #[ ] is evaluated as perl code. #[ ] tags must not be nested (it wouldn't make sense anyway). Show Sample Output
0plexpand() { mkfifo /tmp/plxpnd; $@ </tmp/plxpnd & perl -p -e '$|=1; s/#\[(.*)\]/eval($1)/ge' >/tmp/plxpnd; rm /tmp/plxpnd; } -
HTTP Get, without LWP::Simple Show Sample Output
0perl -MLWP::UserAgent -le 'print LWP::UserAgent->new(requests_redirectable => [])->get(shift)->decoded_content()' "http://dazzlepod.com/ip/me.json" -
cd $target_dir then run the command for fast removal of millions of files
0perl -e 'for(<*>){((stat)[9]<(unlink))}' -
If you have many port mappings, docker ps output becomes pretty illegible. The ~120 char one-liner changes the output into a more readable list of container! Show Sample Output
0docker ps | perl -ple "s/\$/\n\n/g;s/\s{2,}/\n/g;s/(Up)/\\e\[32m\$1\\e\[0m/g;s/(Down)/\\e\[31m\\e\[5m\$1\\e\[25m\\e\[0m/g;s/^([^\n]+)/\\e\[1m\$1\\e\[0m/g;s/(\w+?)$/\\e\[4m\$1\\e\[24m/g" | more -
0perl -MURI::Split=uri_split,uri_join -nle '($s,$a,$p,$q,$f)=uri_split($_);print "$s\t$a\t$p\t$q\t$f"'
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It takes the first value of /prov/loadavg to print that many stars followed by the value. Show Sample Output
0while [ true ]; do cat /proc/loadavg | perl -ne 'm/(^[^ ]+)/; $L = $1; print "*" x $L; print " $L\n";' ; sleep 6; done -
Only the first appearance of a repeated command in the history will be kept. Otherwise, if you prefer to keep last occurrence of a repeated command then maybe you can achieve that by including reverse input/output i.e with 'tac' command in expression above. To see statistics of removed repeated commands:
diff --suppress-common-lines -y ~/.bash_history.bak ~/.bash_history|uniq -c|sort -n|tr -s " "|sed '/^ 1/d'|grep '<'0cp -a ~/.bash_history ~/.bash_history.bak && perl -ne 'print unless $seen{$_}++' ~/.bash_history.bak >~/.bash_history -
0seq 1 9 | perl -MList::Util=shuffle -e 'print shuffle <>;'
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0echo "File;Creator;Producer";find . -name '*.pdf' -print0 | while IFS= read -d $'\0' line;do echo -n "$line;";pdfinfo "$line"|perl -ne 'if(/^(Creator|Producer):\s*(.*)$/){print"$2";if ($1 eq "Producer"){exit}else{print";"}}';echo;done 2>/dev/null
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This script first find all files which contains word xxxxx recursively. Then replace the word xxxxx to yyyyy of the files. Use case: - Web site domain change - Function name change of the program
-1grep -r -l xxxxx . | xargs perl -i -pe "s/xxxxx/yyyyy/g" -
joins multiple lines to create single line with comma separated values. for example if we have an email addresses one per line (copy&paste from spreadsheet) it will oputput one line with comman separated addresses to put it to email client. Show Sample Output
-1perl -le 'print join ", ", map { chomp; $_ } <>' -
-1find . -name "*.jpg" | perl -ne'chomp; $name = $_; $quote = chr(39); s/[$quote\\!]/_/ ; print "mv \"$name\" \"$_\"\n"'
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-1perl -e 'print scalar localtime $ARGV[0],"\n" ' epoch
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This command will replace all instances of 'foo' with 'bar' in all files in the current working directory.
-1perl -pi -e 's/foo/bar/g' $(grep -l foo ./*) -
This command will replace all instances of 'foo' with 'bar' in all files in the current working directory and any sub-directories.
-1perl -pi -e 's/foo/bar/g' $(grep -rl foo ./*) -
if you want to only print the IP address from a file. In this case the file will be called "iplist" with a line like "ip address 1.1.1.1" it will only print the "1.1.1.1" portion
-1perl -wlne 'print $1 if /(([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5]))/' iplist -
Uses curl to download page of membership of US Congress. Use sed to strip HTML then perl to print a line starting with two tabs (a line with a representative) Show Sample Output
-1curl "http://www.house.gov/house/MemberWWW.shtml" 2>/dev/null | sed -e :a -e 's/<[^>]*>//g;/</N;//ba' | perl -nle 's/^\t\t(.*$)/ $1/ and print;' -
-1perl -i -ne 'print uc $_' $1
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-1find . -type f | perl -lne 'print if -T;' | xargs egrep "somepattern"
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This command prints all lines of a file together with is line number. Show Sample Output
-1perl -ne 'print "$. - $_"' infile.txt -
-1find -name ".php" -exec perl -pi -e 's/search/replace/g/' {} \;
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Find the length of the longest line of code in your files. Show Sample Output
-1perl -ne 'push(@w, length); END {printf "%0d\n" , (sort({$b <=> $a} @w))[0]}' *.cpp -
Based on the execute with timeout command in this site. A more complex script: #!/bin/sh # This script will check the avaliability of a list of NFS mount point, # forcing a remount of those that do not respond in 5 seconds. # # It basically does this: # NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH) # TIMEOUT=5 SCRIPT_NAME=$(basename $0) for i in $@; do echo "Checking $i..." if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2 echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2 umount -fl $i; echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2 mount $i; fi done
-1NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH) -
-1ifconfig eth0 | perl -ne 'print $1 if m/addr:((?:\d+\.){3}\d+)/'
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This will list all symlinks that are directories under the current directory. This will help you distinguish them from regular files.
-1ls -l $(find ./ -type l | perl -ne 'chomp; if (-d) { print "$_\n" }') - ‹ First < 11 12 13 14 15 >
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