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 12
  • 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 7
  • 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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Remove ( color / special / escape / ANSI ) codes, from text, with sed
Remove ( color / special / escape / ANSI ) codes, from text, with sed Credit to the original folks who I've copied this command from. The diff here is: Theirs: [m|K] Theirs is supposed to remove \E[NUMBERS;NUMBERS[m OR K] This statement is incorrect in 2 ways. 1. The letters m and K are two of more than 20+ possible letters that can end these sequences. 2. Inside []'s , OR is already assumed, so they are also looking for sequences ending with | which is not correct. This : [a-zA-Z] This resolves the "OR" issue noted above, and takes care of all sequences, as they all end with a lower or upper cased letter. This ensures 100% of any escape code 'mess' is removed.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Generate MD5 of string and output only the hash checksum in a readable format
Generates the md5 hash, without the trailing " -" and with the output "broken" into pairs of hexs.

Unrar multiple directories into current working directory
Grabs all rar files in any current subdirectories and feeds it to unrar. Doesn't work well with things packaged like file.part01.rar. Works best with File.rar. You can recurse into other directories by adding more /*'s

RTFM function
Some commands have more information on 'info' than in the man pages

pinky - user info
Gives information about user's home directory and real name and shell user is having.

List the Sizes of Folders and Directories

Check motherboard manufacturer, product name, version and serial number
Very slick way to check your motherboard manufacturer, product name, version and serial number.

Top ten (or whatever) memory utilizing processes (with children aggregate)
This command loops over all of the processes in a system and creates an associative array in awk with the process name as the key and the sum of the RSS as the value. The associative array has the effect of summing a parent process and all of it's children. It then prints the top ten processes sorted by size.


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