Commands by StefanLasiewski (6)

  • Use GNU info with a pager

    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 8
  • Find Man pages for everything in your $PATH

    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 5
  • 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 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 8
  • Print a date from 3 days ago

    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 11
  • Delete the previous entry in your history

    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 11
  • Read info(1) pages using 'less' instead of GNU Texinfo

    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 32

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Display the standard deviation of a column of numbers with awk
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.

List 10 largest directories in current directory
du -m option to not go across mounts (you usually want to run that command to find what to destroy in that partition) -a option to also list . files -k to display in kilobytes sort -n to sort in numerical order, biggest files last tail -10 to only display biggest 10

Print all lines in a file that are not a certain length
Alternatively, print all the lines that are a certain length: $awk 'length($0)==12 {print}' your_file_name

vi a new file with execution mode
$ vix /tmp/script.sh Open a file directly with execution permission. Put the function in your .bashrc You can also put this in your vimrc: $ command XX w | set ar | silent exe "!chmod +x %" | redraw! and open a new file like this: $ vi +XX /tmp/script.sh

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Get full directory path of a script regardless of where it is run from
Also resolves symlinks, showing the full path of the link target

Remove embedded fonts from a pdf.
It's sometimes useful to strip the embedded fonts from a pdf, for importing into something like Inkscape. Be warned, this will increase the size of a pdf substantially. I tried this with only gs writing with -sDEVICE=pdfwrite but it doesn't seem to work, so I just pipe postscript output to ps2pdf for the same effect.

Colored status of running services
Replace service --status-all 2>&1 by service --status-all 2>/dev/null to hide all services with the status [ ? ]

Adding Color Escape Codes to global CC array for use by echo -e
I was looking for the fastest way to create a bunch of ansi escapes for use in echo -e commands throughout a lot of my shell scripts. This is what I came up with, and I actually stick that loop command in a function and then just call that at the beginning of my scripts to not clutter the environment with these escape codes, which can wreck havok on my terminal when I'm dumping the environment. More of a cool way to store escape ansi codes in an array. You can echo them like: $ echo -e "${CC[15]}This text is black on bright green background." I usually just use with a function: $ # setup_colors - Adds colors to array CC for global use $ # 30 - Black, 31 - Red, 32 - Green, 33 - Yellow, 34 - Blue, 35 - Magenta, 36 - Blue/Green, 37 - White, 30/42 - Black on Green '30\;42' $ function setup_colors(){ declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7));CC[$i]="\033[1;3${i}m";CC[$ii]="\033[0;3${i}m";done;CC[15]="\033[30;42m"; export R='\033[0;00m';export X="\033[1;37m"; }; $ export -f setup_colors CC[15] has a background of bright green which is why it is separate. R resets everything, and X is my default font of bright white. $ CC[15]="\033[30;42m"; R=$'\033[0;00m'; X=$'\033[1;37m' Those are just my favorite colors that I often use in my scripts. You can test which colors by running $ for i in $(seq 0 $((${#CC[@]} - 1))); do echo -e "${CC[$i]}[$i]\n$R"; done See: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html for more usage.

Get your default route
This gets you your default route programatically, useful for scripts

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