Commands by ExtremeMultiman (1)

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burn initial session on a growable DVD using growisofs
replace "directory name to burn on DVD" with actual directory name that you want to copy on DVD

Capture data in ASCII. 1500 bytes
Sniffing traffic on port 80 only the first 1500 bytes

Quickly generate an MD5 hash for a text string using OpenSSL
Thanks to OpenSSL, you can quickly and easily generate MD5 hashes for your passwords. Alternative (thanks to linuxrawkstar and atoponce): $ echo -n 'text to be encrypted' | md5sum - Note that the above method does not utlise OpenSSL.

Get duration of an audio file in seconds.
This is an alternative to #9131. ffmpeg didn't work on my .au files, though it did on the .wav ones. Also useful if you don't have ffmpeg but do have sox. Handily, sox already reports in seconds (decimal).

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Test http request every second, fancy display.
Use the command watch, which is really hard to pass nested quotes to, and insert newlines where they are supposed to go in the HTTP request. that is after 1.1 after the host and two newlines at the end before the EOF. i use this all day what? no support for HEREDOCs on commandlinefu's interface? need more fu.

Change timestamp on a file
-a for access time, -m for modification time, -c do not create any files, -t timestamp

Change pidgin status
Changes pidgin status using its dbus interface. The status code can be obtained using command #4543.

DELETE all those duplicate files but one based on md5 hash comparision in the current directory tree
This one-liner will the *delete* without any further confirmation all 100% duplicates but one based on their md5 hash in the current directory tree (i.e including files in its subdirectories). Good for cleaning up collections of mp3 files or pictures of your dog|cat|kids|wife being present in gazillion incarnations on hd. md5sum can be substituted with sha1sum without problems. The actual filename is not taken into account-just the hash is used. Whatever sort thinks is the first filename is kept. It is assumed that the filename does not contain 0x00. As per the good suggestion in the first comment, this one does a hard link instead: $ find . -xdev -type f -print0 | xargs -0 md5sum | sort | perl -ne 'chomp; $ph=$h; ($h,$f)=split(/\s+/,$_,2); if ($h ne $ph) { $k = $f; } else { unlink($f); link($k, $f); }'

Check if a process is running
Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.


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