Commands tagged readelf (1)

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Verbosely delete files matching specific name pattern, older than 15 days.

grep expression (perl regex) to extract all ip addresses from both ip and ifconfig commands output
It uses the following GNU grep options: "-o" which shows only the matching part of the line and "-P" which allows the use of Perl regular expressions.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Remove all but One
$ rm-but() { ls -Q | grep -v "$1" | xargs rm -r ; } Add this to your .bashrc file. Then whenever you need to remove all files/directories but one from present working directory. Run: $ rm-but Notes: 1. This doesn't affect the hidden files. 2. Argument is actually as string. And all files/directories having this string in there name are left untouched.

List all duplicate directories
Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical. if in doubt apply: $ diff -rq path_to_dir1 path_to_dir2 AWK function taken from here: http://stackoverflow.com/questions/2912224/find-duplicates-lines-based-on-some-delimited-fileds-on-line

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6` Modern systems need higher strenght, so add some special characters: # < /dev/urandom tr -dc '[email protected]#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8

Don't spam root. Log your cronjob output to syslog
This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to [email protected] (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

Stop or Start (Restart) a Windows service from a Linux machine
Control (stop, start, restart) a Windows Service from a Linux machine which has the `net` command (provided by samba).

Copy a file using pv and watch its progress
pv allows a user to see the progress of data through a pipeline, by giving information such as time elapsed, percentage completed (with progress bar), current throughput rate, total data transferred, and ETA. (man pv)

Determine status of a RAID write-intent bitmap
Report information about a bitmap file.


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