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 11
  • 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 6
  • 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 5
  • 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 9
  • 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 3
  • 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 9

  • 5
    awk '/match/{print NR}' file
    inof · 2009-06-03 17:34:13 7

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disable history for current shell session

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"

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"

Get a docker container's run command line
A good way to build a new container when you don't remember how you did it the first time

First pass dvd rip... The set of commands was too long, so I had to separate them into two.
This set of commands will rip a dvd title using a 2 pass mencoder xvid encode. It will provide a great quality rip. It will rip as close to 700MB as possible. (note the bitrate of -700000) Enjoy!

fast access to any of your favorite directory.
example: -------------------------------------------------------------------------------------------- user@ubuntu:~/workspace/SVN/haystak-repos/trunk/internal/src$ addpi -------------------------------------------------------------------------------------------- Now that directory is in the list of fast access directories. You can switch to it anytime like this: -------------------------------------------------------------------------------------------- user@ubuntu:~$ pi internal` user@ubuntu:~/workspace/SVN/haystak-repos/trunk/internal/src$ -------------------------------------------------------------------------------------------- Please note the backquote ( the symbol that shares its key with ~ in the keyboard ) pi will switch you to that directory. To see the list of all fast access directories you have to say "cat ~/.pi"

Selecting a random file/folder of a folder
random file from files in directory

Insert a line at the top of a text file without sed or awk or bash loops
Just use '-' to use STDIN as an additional input to 'cat'

Restore deleted file from GIT repository
This command will automatically find the latest version of the file that was deleted and restore it to it's previous location. If, of course, your file was kept in a git repository... I found this command on http://stackoverflow.com/a/1113140

Rename HTML files according to their title tag
The above one-liner could be run against all HTML files in a directory. It renames the HTML files based on the text contained in their title tag. This helped me in a situation where I had a directory containing thousands of HTML documents with meaningless filenames.


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