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Commands by DEinspanjer

Commands by DEinspanjer from sorted by
Terminal - Commands by DEinspanjer - 9 results
some_cronjobed_script.sh 2>&1 | tee -a output.log | grep -C 1000 ERROR
2009-03-06 17:51:13
User: DEinspanjer
Functions: grep tee
Tags: Linux
-1
Up
Down
Log output from a cronjob to a file, but also e-mail if a string is found

The large context number (-C 1000) is a bit of a hack, but in most of my use cases, it makes sure I'll see the whole log output.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
zcat a_big_file.gz | sed -ne "$(zcat a_big_file.gz | tr -d "[:print:]" | cat -n | grep -vP "^ *\d+\t$" | cut -f 1 | sed -e "s/\([0-9]\+\)/\1=;\1p;/" | xargs)" | tr -c "[:print:]\n" "?"
2009-02-24 02:57:37
User: DEinspanjer
Functions: sed tr zcat
1
Up
Down
Scan a gz file for non-printable characters and display each line number and line that contains them.

Scans the file once to build a list of line numbers that contain non-printable characters

Scans the file again, passing those line numbers to sed as two commands to print the line number and the line itself. Also passes the output through a tr to replace the characters with a ?

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
rsync -Pz user@remotehost:/path/file.dat .
2009-02-20 20:13:59
User: DEinspanjer
Functions: rsync
1
Up
Down
Copy a file from a remote server to your local box using on-the-fly compression

-P displays a progress meter

-z tells rsync to use compression

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
trap "echo \"$0 process $$ killed on $(date).\"; exit " HUP INT QUIT ABRT TERM STOP
2009-02-18 23:58:58
User: DEinspanjer
Functions: trap
2
Up
Down
Simple example of the trap command
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
(cd /Applications/Firefox.app/Contents/MacOS; ./firefox-bin -p default --no-remote)
2009-02-18 21:35:02
User: DEinspanjer
Functions: cd
-1
Up
Down
Run a second copy of Firefox using the same profile on Mac OS X
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
psg() { if [ -z "$2" ]; then psargs="aux"; greparg="$1"; else psargs="$1"; greparg="$2"; fi; ps $psargs | grep -i "$(echo $greparg | sed -e 's/^\(.\)/[\1]/')\|^$(ps $psargs | head -1)" ; }
2009-02-18 20:57:17
User: DEinspanjer
Functions: grep ps
0
Up
Down
psg (ps grep) function if you don't have pgrep or don't know how to use it

My variant on this common function. Some highlights:

Allows you to override the default ps args of "aux"

Uses bracket trick to omit the grep process itself without having to use a second grep

Always prints the correct header row of ps output

Limitations: Ugly ps error output if you forget to quote your multi word grep argument

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
trap "echo \"$0 process $$ killed on $(date).\" | tee ${0##*/}_$$_termination.log; echo 'Active processes at the time were logged to ${0##*/}_$$_termination.log'; ps u >> ${0##*/}_$$_termination.log; exit " HUP INT QUIT ABRT TERM STOP
2009-02-18 20:13:29
User: DEinspanjer
Functions: trap
1
Up
Down
A signal trap that logs when your script was killed and what other processes were running at that time

trap is the bash builtin that allows you to execute commands when the current script receives a particular signal.

Uses $0 for the script name, $$ for the script PID, tee to output to STDOUT as well as a log file and ps to log other running processes.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
unset files i; set -f; O=$IFS; while IFS= read -r -d $'\0' files[i++]; do :; done < <(find . -name '*.avi' -print0) && IFS=$O; set +f && echo "Running: mplayer \"${files[ $(( $RANDOM % ${#files[@]} )) ]}\""
2009-02-18 16:53:57
User: DEinspanjer
Functions: echo find read set unset
0
Up
Down
Play a random .avi file from a media tree

unsets variables used by the one-liner

sets up the IFS bash variable to not be affected by whitespace and disables extra glob expansion

uses read to slurp the results of the find command into an array

selects an element of the array at random to be passed as an argument to mplayer

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat ~/.ssh/id_rsa.pub | ssh user@machine "mkdir ~/.ssh; cat >> ~/.ssh/authorized_keys"
2009-02-05 19:37:56
User: DEinspanjer
Functions: cat ssh
35
Up
Down
Copy your ssh public key to a server from a machine that doesn't have ssh-copy-id

If you use Mac OS X or some other *nix variant that doesn't come with ssh-copy-id, this one-liner will allow you to add your public key to a remote machine so you can subsequently ssh to that machine without a password.

Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate