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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Generate an XKCD #936 style 4 word passphrase (fast)
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Copy something to multiple SSH hosts with a Bash loop
Just a quick and simple one to demonstrate Bash For loop. Copies 'file' to multiple ssh hosts.

sort list of email addresses by domain.tld
email random list can be created here: https://www.randomlists.com/email-addresses

clear the X clipboard
Clears your clipboard if xsel is installed on your machine. If your xsel is dumb, you can also use $xsel --clear --clipboard

list files recursively by size

Move a folder and merge it with another folder
This will move a folder and merge it with another folder which may contain duplicates. Technically it's just creating hardlinks of everything in the folder, and after it's done, delete the source (with rm -r source/ ) to complete the move. This is much faster than, for example, using rsync to merge folders which would actually copy the entire contents and so for a lot of files would take much longer. This uses macutils gcp port of cp so it can be used on osx/MacOS. If using in linux or some unix where cp includes the ability to create links with -l you can just use cp instead of gcp.

Retrieve "last modified" timestamp of web resource in UTC seconds
This command line assumes that "${url}" is the URL of the web resource. It can be useful to check the "freshness" of a download URL before a GET request.

check open ports without netstat or lsof

Apply, in parallel, a bc expression to CSV
Define a function that applies bc, the *nix calculator, with the specified expression to all rows of the input CSV. The first column is mapped to {1}, second one to {2}, and so forth. See sample output for an example. This function uses all available cores thanks to GNU Parallel. Requires GNU Parallel

List programs with open ports and connections
I prefer to use this and not the -n variety, so I get DNS-resolved hostnames. Nice when I'm trying to figure out who's got that port open.


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