Commands using file (166)

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Insert commas to make reading numbers easier in the output of ls
This modifies the output of ls so that the file size has commas every three digits. It makes room for the commas by destructively eating any characters to the left of the size, which is probably okay since that's just the "group".   Note that I did not write this, I merely cleaned it up and shortened it with extended regular expressions. The original shell script, entitled "sl", came with this description:    : '  : For tired eyes (sigh), do an ls -lF plus whatever other flags you give  : but expand the file size with commas every 3 digits. Really helps me  : distinguish megabytes from hundreds of kbytes...  :  : Corey Satten, corey@cac.washington.edu, 11/8/89  : '   Of course, some may suggest that fancy new "human friendly" options, like "ls -Shrl", have made Corey's script obsolete. They are probably right. Yet, at times, still I find it handy. The new-fangled "human-readable" numbers can be annoying when I have to glance at the letter at the end to figure out what order of magnitude is even being talked about. (There's a big difference between 386M and 386P!). But with this nifty script, the number itself acts like a histogram, a quick visual indicator of "bigness" for tired eyes. :-)

read squid logs with human-readable timestamp

Output a SSL certificate start or end date
A quick and simple way of outputting the start and end date of a certificate, you can simply use 'openssl x509 -in xxxxxx.crt -noout -enddate' to output the end date (ex. notAfter=Feb 01 11:30:32 2009 GMT) and with the date command you format the output to an ISO format. For the start date use the switch -startdate and for end date use -enddate.

list block devices
Shows all block devices in a tree with descruptions of what they are.

replace spaces in filenames with underscores
This command will replace all the spaces in all the filenames of the current directory with underscores. There are other commands that do this here, but this one is the easiest and shortest.

Set pcap & SUID Bit for priv. network programs (like nmap)

Download entire commandlinefu archive to single file
'jot' does not come with most *nix distros, so we need to use seq to make it work. This version tested good on Fedora 11.

List all installed Debian packages
Should work on all systems that use dpkg and APT package management.

Turn white color to transparent for a series of png images
mogrify can be used like convert. The difference is that mogrify overwrites files: http://www.imagemagick.org/www/mogrify.html Of course, other source colors can be used as well.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.


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