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Commands by DoNotRememberMe from sorted by
Terminal - Commands by DoNotRememberMe - 8 results
CMD="who";SEC=1;N=0;OLD="";NEW=""; while `sleep $SEC`; do OLD="$NEW"; NEW="$(eval $CMD)"; DIFF=`diff <( echo "$OLD" ) <( echo "$NEW" )`; if [ -n "$DIFF" ]; then date; echo "Diff #$N (${SEC}s): $CMD"; echo "$DIFF"; fi; N=$[$N+1]; done | tee /tmp/keepr
2010-11-15 19:55:39
Functions: echo tee
0

Watch any command (pipes ok, quotes be careful) and keep history in a file. Good for watching and recording any kind of status or error condition, file creations, etc. The choice of "who" as CMD was just to show an obvious usage.

Uses plenty of shell tricks that can be disassembled for simpler stuff. It's deliberately not perfect, but it is generic, and can be customized for your own uses. Had to shorten a little to meet 255 chars.

Better than "watch" how? It keeps a date log of what is going on, and tee'd output is plain-text.

seq -s" " -50 -1 | tr -dc -
2010-03-25 06:00:24
Functions: seq tr
5

Get there by going backwards and forgetting the numbers.

rpm --querytags | egrep -v HEADERIMMUTABLE | sort | while read tag ; do rpm -q --queryformat "$tag: [%{$tag} ]\n" -p $SomeRPMfile ; done
2010-03-25 05:40:48
Functions: egrep read rpm sort
0

If you want to relocate a package on your own, or you just want to know what those PREIN/UN and POSTIN/UN scripts will do, this will dump out all that detail simply.

You may want to expand the egrep out other verbose flags like CHANGELOGTEXT etc, as your needs require.

It isn't clear, but the formatting around $tag is important: %{$tag} just prints out the first line, while [%{$tag }] iterates thru multi-line output, joining the lines with a space (yes, there's a space between the g and } characters. To break it out for all newlines, use [%{$tag\n}] but the output will be long.

This is aside from rpm2cpio | cpio -ivd to extract the package files.

OUTPUT="`find / -type f`" ; echo "$OUTPUT" | grep sysrq ; echo "$OUTPUT" | grep sysctl ; echo "$OUTPUT" | less
2010-03-25 05:02:10
Functions: echo grep sysctl
0

The example is a little bit bogus, but applies to any command that takes a while interactively, or might be a bit of a drag on system resources. Once the command's output is saved to a variable, you can then echo "$OUTPUT" to see it in multi-line glory after that. The use of double-quotes around the backticks and during the variable expansion disables any IFS conversion during those two operations.

Very useful for reporting that might pull different lines out, like from dmidecode, inq or any other disk detail command. The only caveat is that storing too much in a variable might make your shell process grow.

( zcat $FILE || gzcat $FILE || bzcat2 $FILE ) | less
2010-03-17 03:14:48
Functions: zcat
5

Something to stuff in an alias when you are working in multiple environments. The double-pipe OR will fall through until one of the commands succeeds, and the rest won't be executed. Any STDERR will fall out, but the STDOUT from the correct command will bubble out of the parenthesis to the less command, or some other command you specify.

find ${PATH//:/ } -name \*bash\*
2010-03-16 04:26:27
Functions: find
6

Searches your $PATH for whatever you substitute for bash, though not sure if this will work if you substitute a different shell for bash!

( last ; ls -t /var/log/wtmp-2* | while read line ; do ( rm /tmp/wtmp-junk ; zcat $line 2>/dev/null || bzcat $line ) > /tmp/junk-wtmp ; last -f /tmp/junk-wtmp ; done ) | less
2010-03-16 04:17:16
Functions: last ls read rm zcat
5

When your wtmp files are being logrotated, here's an easy way to unpack them all on the fly to see more than a week in the past. The rm is the primitive way to prevent symlink prediction attack.

( du -xSk || du -kod ) | sort -nr | head
2010-03-16 04:05:14
Functions: du sort
4

No need to type out the full OR clause if you know which OS you're on, but this is easy cut-n-paste or alias to get top ten directories by singleton.

To avoid the error output from du -xSk you could always 2>/dev/null but you might miss relevant STDERR.