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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

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.

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

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 ?

rsync -Pz user@remotehost:/path/file.dat .
trap "echo \"$0 process $$ killed on $(date).\"; exit " HUP INT QUIT ABRT TERM STOP
(cd /Applications/Firefox.app/Contents/MacOS; ./firefox-bin -p default --no-remote)
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

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

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

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.

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

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

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
45

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.