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Get max number of arguments
Get max number of arguments that can be accepted by the exec() system call.

Break lines after, for example 78 characters, but don't break within a word/string
Per default, linux/unix shells are configured with a width of 80 characters. If you like to edit a phrase or string on a line with more than 80 characters it might take long to go there (for example a line with 1000 characters and you like to edit the 98th word which is character 598-603). Maybe you might wish to use 78 characters, because if you forward the text via mail and the text will be quoted (2 extra characters at the beginning to the line "> "), you use 80 characters, otherwise 82, which are lame.

Display GCC Predefined Macros
doesn't need /dev/null

Easy file sharing from the command line using transfer.sh
Requires: curl xsel access to the internet(http://transfer.sh) This is an alias utilizing the transfer.sh service to make sharing files easier from the command line. I have modified the alias provided by transfer.sh to use xsel to copy the resulting URL to the clipboard. The full modified alias is as follows since commandlinefu only allows 255 characters: transfer() { if [ $# -eq 0 ]; then echo "No arguments specified. Usage:\necho transfer /tmp/test.md\ncat /tmp/test.md | transfer test.md"; return 1; fi if tty -s; then basefile=$(basename "$1" | sed -e 's/[^a-zA-Z0-9._-]/-/g'); curl --progress-bar --upload-file "$1" "https://transfer.sh/$basefile" |xsel --clipboard; else curl --progress-bar --upload-file "-" "https://transfer.sh/$1" |xsel --clipboard ; fi; xsel --clipboard; }

Content search.
Grep will read the contents of each file in PWD and will use the REs $1 $2 ... $n to match the contents. In case of match, grep will print the appropriate file, line number and the matching line. It's just easier to write $ ff word1 word2 word3 Instead of $ grep -rinE 'word1|word2|word3' .

Create multiple subfolders in one command.
Instead of typing separate commands to create various subfolders, we can create multiple subfolders by listing them between brackets and separated by commas.

One-liner to generate Self-Signed SSL Certificate+Key without any annoying prompts or CSRs
Handy if you want to quickly generate a self-signed certificate. Also can be used in your automated scripts for generating quick-use certificates.

Stream system sounds over rtmp
sox (SOund eXchange) can capture the system audio be it a browser playing youtube or from hardware mic and can pipe it to ffmpeg which encodes it into flv and send it over rtmp. Tested using Red5 rtmp server.

Add SVN keywords property to all PHP and Javascript files

Encode file path to URL
Really helpfull when play with files having spaces an other bad name. Easy to store and access names and path in just a field while saving it in a file. This format (URL) is directly supported by nautilus and firefox (and other browsers)


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