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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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An improved version of http://www.commandlinefu.com/commands/view/1772/simple-countdown-from-a-given-date that uses Perl to pretty-print the output. Note that the GNU-style '--no-title' option has been replaced by its one-letter counterpart '-t'.
This command will replace all instances of 'foo' with 'bar' in all files in the current working directory and any sub-directories.
This command will replace all instances of 'foo' with 'bar' in all files in the current working directory.
Many Mac OS X programs, especially those in Microsoft:Office, create ASCII files with lines terminated by CRs (carriage returns). Most Unix programs expect lines separated by NLs (newlines). This little command makes it trivial to convert them.
Finds all directories containing more than 99MB of files, and prints them in human readable format. The directories sizes do not include their subdirectories, so it is very useful for finding any single directory with a lot of large files.
This command will display all lines between 2 patterns: word-a and word-b
useful for grepping command outputs from file
Finds the string in every file in an entire directory and all its subdirectories and replaces it with a new string. Especially useful when changing a machine's IP address or hostname - run it on /etc.
Probably only works with GNU du and modern perls.
The Linux /dev/full file simulates a "disk full" condition, and can be used to verify how a program handles this situation.
In particular, several programming language implementations do not print error diagnostics (nor exit with error status) when I/O errors like this occur, unless the programmer has taken additional steps. That is, simple code in these languages does not fail safely. In addition to Perl, C, C++, Tcl, and Lua (for some functions) also appear not to fail safely.
MIME::Base64 is a part of Perl5 distribution. You can also use decode_base64 for oposite result.
self explanatory see sample output
Insert a comma where necessary when counting large numbers. I needed to separate huge amounts of packets and after 12+ hours of looking in a terminal, I wanted it in readable form.
Adds a newline to the end of all cpp files in the directory to avoid warnings from gcc compiler.
That "^M" is Ctrl-M, which is a carriage return, and is not needed in Unix file systems.
Where ^V is actually Ctrl-V and ^M is actually Ctrl-M (you must type these yourself, don't just copy and paste this command). ^V will not be displayed on your screen.