Commands by inof (7)

  • Some commands (such as sed and perl) have options to support in-place editing of files, but many commands do not. This shell function enables any command to change files in place. See the sample output for many examples. The function uses plain sh syntax and works with any POSIX shell or derivative, including zsh and bash. Show Sample Output


    1
    inplace() { eval F=\"\$$#\"; "$@" > "$F".new && mv -f "$F".new "$F"; }
    inof · 2010-04-09 11:36:31 8
  • Several people have submitted commands to do this, but I think this is the simplest solution. It also happens to be the most portable one: It should work with any sh or csh derived shell under any UNIX-like OS. Oh by the way, with my German locale ($LC_TIME set appropriately) it prints "g" most of the time, and sometimes (on Wednesdays) it prints "h". It never prints "y". Show Sample Output


    3
    date +%A | tail -2c
    inof · 2010-04-08 15:14:06 0
  • That one works on Linux. On BSD and Solaris, the ifconfig output is much easier to parse: /sbin/ifconfig -a | awk '/inet/{print $2}'


    0
    /sbin/ifconfig | awk -F'[ :]+' '/inet addr/{print $4}'
    inof · 2009-07-21 14:18:17 2
  • This is *NOT* about the -i option in grep. I guess everybody already knows that option. This is about the basic rule of life that the simplest things are sometimes the best. ;-) One day when I used "grep -i" for the umpteenth time, I decided to make this alias, and I've used it ever since, probably more often than plain grep. (In fact I also have aliases egrip and fgrip defined accordingly. I also have wrip="grep -wi" but I don't use this one that often.) If you vote this down because it's too trivial and simplistic, that's no problem. I understand that. But still this is really one of my most favourite aliases.


    -2
    alias grip="grep -i"
    inof · 2009-07-21 11:12:15 2
  • This alias finds identical lines in a file (or pipe) and prints a sorted count of them (the name "sucs" descends from the first letters of the commands). The first example shows the number of logins of users; the one who logged in most often comes last. The second example extracts web client IP addresses from a log file, then pipes the result through the "sucs" alias to find out which clients are performing the most accesses. Or pipe the first column of ps(1) output through "sucs" to see how many processes your users are running. Show Sample Output


    0
    alias sucs="sort | uniq -c | sort -n"
    inof · 2009-07-21 10:55:06 0
  • This shell snippet reads a single keypress from stdin and stores it in the $KEY variable. You do NOT have to press the enter key! The key is NOT echoed to stdout! This is useful for implementing simple text menus in scripts and similar things.


    5
    stty cbreak -echo; KEY=$(dd bs=1 count=1 2>/dev/null); stty -cbreak echo
    inof · 2009-06-09 13:15:49 4

  • 5
    awk '/match/{print NR}' file
    inof · 2009-06-03 17:34:13 3

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total percentage of memory use for all processes with a given name
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Create a tar archive using 7z compression
Using 7z to create archives is OK, but when you use tar, you preserve all file-specific information such as ownership, perms, etc. If that's important to you, this is a better way to do it.

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"

count match string lines from file(s)

E-mail a traditional Berkeley mbox to another recipient as individual e-mails.

Don't save commands in bash history (only for current session)
Unsetting HISTFILE avoid getting current session history list saved.

Unlock your KDE4.3 session remotely
The unlock command for KDE 4.3 has changed from krunner_lock, this process doesn't exist anymore. So here's the update :-) If qdbus complains about not being able to find X, put a "DISPLAY=:0 " (:0 being your X server display) in front of the command.

display emerge.log date in a human friendly way
gentoo only or gentoo-like linux distributions.

ping a range of IP addresses
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Stream audio over ssh
This will allow you to convert an audio file to wav format, and send it via ssh to a player on the other computer, which will open and play it there. Of course, substitute your information for the sound file and remote address You do not have to use paplay on the remote end, as it is a PulseAudio thing. If the remote end uses ALSA, you should use aplay instead. If it uses OSS, you should berate them about having a lousy sound system. Also, you're not limited to transmitting encoded as wav either, it's just that AFAIK, most systems don't come with mp3 codecs, but will play wav files fine. If you know SoX is installed on the remote end and has mp3 codecs, you can use the following instead: $ cat Klaxon.mp3 |ssh thelab@company.com play -t mp3 - this will transmit as mp3. Again, use your specific information. if you're not playing mp3s, use another type with the -t option


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