Commands by StefanLasiewski (6)

  • This command is similar to the above, but is much simpler to remember. Sure, it's isn't as precise as the parent command, but most people aren't going to remember those --flags anyways unless you stick it into your .bashrc on every single system that you manage. Show Sample Output


    0
    info foo |less
    StefanLasiewski · 2013-09-12 16:49:08 0
  • If I type 'man something', I want it to find the manpage in the same order as my PATH. You can add something like this to your .bashrc # # Add my MacPorts, my personal utilities and my company utilities to my PATH. export PATH=$PATH:/opt/local/bin:$HOME/bin:/our_company_utils/bin/ # Now set the manpath based on the PATH, after man(1) parses man.conf # - No need to modify man.conf or manually modify MANPATH_MAP # - Works on Linux, FreeBSD & Darwin, unlike /etc/manpaths.d/ # Must unset MANPATH first. MANPATH is set on some systems automatically (Mac), # which causes manpath to ignore the values of PATH like /opt/local/bin (MacPorts). # Also MANPATH may be deprecated. See "SEARCH PATH FOR MANUAL PAGES" in man(1) unset MANPATH # manpath acts differently on Solaris, FreeBSD, MacOSX & GNU. This works everywhere. manpath >/dev/null # Note that MacOSX, FreeBSD & Linux have fancier ways to do some of this. (e.g. 'man --path' or 'man -q'), but this command is more universal and should work everywhere. Show Sample Output


    0
    unset MANPATH; manpath >/dev/null
    StefanLasiewski · 2010-07-02 19:45:27 0
  • 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 root@localhost (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 Show Sample Output


    6
    */5 * * * * root /usr/local/nagios/sbin/nsca_check_disk 2>&1 |/usr/bin/logger -t nsca_check_disk
    StefanLasiewski · 2010-07-02 00:47:05 2
  • This command prints the Date (Not time) from 3 days ago (72 hours ago). This works on systems without GNU date (MacOSX , Solaris, FreeBSD). Show Sample Output


    4
    TZ=PST8PDT+72 date '+%Y_%m_%d'
    StefanLasiewski · 2010-07-02 00:29:27 6
  • I rarely need this, but I have a hard time remembering the command when I need it. Admit it. This has happened to you. Yes this is bad, and you better clean up now. Borrowed from http://thoughtsbyclayg.blogspot.com/2008/02/how-to-delete-last-command-from-bash.html Show Sample Output


    0
    alias histdel='history -d $((HISTCMD-2)) && history -d $((HISTCMD-1))'
    StefanLasiewski · 2010-07-02 00:20:44 3
  • I like man pages, and I like using `less(1)` as my pager. However, most GNU software keeps the manual in the 'GNU Texinfo' format, and I'm not a fan of the info(1) interface. Just give me less. This command will print out the info(1) pages, using the familiar interface of less! Show Sample Output


    1
    info gpg |less
    StefanLasiewski · 2010-07-01 23:44:15 2

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Check if a web page has changed last time checked.
Checks if a web page has changed. Put it into cron to check periodically. Change http://www.page.de/test.html and mail@mail.de for your needs.

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

exec chmod to subfiles
Using `-exec cmd {} +` causes find to build the command using all matching filenames before execution, rather than once per file.

Keep a copy of the raw Youtube FLV,MP4,etc stored in /tmp/
Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.

Find broken symlinks in the current directory and its subdirectories.
This is best run as root to avoid permission denials that can produce false positives. Obviously you can specify a directory in the usual way: $ find -L dirname -type l I can't remember where I read about this or who deserves the credit for it. The find(1) manual page hints strongly toward it, however.

Outputs a 10-digit random number

archlinux: shows list of packages that are no longer needed
Shows a list of packages which are no longer needed as dependencies of any package installed on your system.

Display the size of all your home's directories
Display the size (human reading) of all the directories in your home path (~).

geoip information
Not my script. Belongs to mathewbauer. Used without his permission. This script gives a single line as shown in the sample output. NOTE: I have blanked out the IP address for obvious security reasons. But you will get whatever is your IP if you run the script. Tested working in bash.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested


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