Commands using file (166)

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command! -nargs=1 Vs vs <args>
Because entering ':' requires that you press shift, sometimes common command-line / mini-buffer commands will be capitalized by accident.

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.

Number of .... indicate how far down to cd
Use dots to cd down directories instead of having to remember all of the pesky back slashes! Better yet, works on even and odd number of dots! Now, just estimate how far down you want to traverse.

connect via ssh using mac address
Instead of looking for the right ip address, just pick whatever address you like and set a static ip mapping.

Compress and store the image of a disk over the network
Create an image of "device" and send it to another machine through the network ("target" and "port" sets the ip and port the stream will be sent to), outputting a progress bar On the machine that will receive, compress and store the file, use: $nc -l -p | 7z a -si -m0=lzma2 -mx=9 -ms=on Optionally, add the -v4g switch at the end of the line in order to split the file every 4 gigabytes (or set another size: accepted suffixes are k, m and g). The file will be compressed using 7z format, lzma2 algorithm, with maximum compression level and solid file activated. The compression stage will be executed on the machine which will store the image. It was planned this way because the processor on that machine was faster, and being on a gigabit network, transfering the uncompressed image wasn't much of a problem.

Scan all open ports without any required program

Function that outputs dots every second until command completes
Very useful in shell scripts because you can run a task nicely in the background using job-control and output progress until it completes. Here's an example of how I use it in backup scripts to run gpg in the background to encrypt an archive file (which I create in this same way). $! is the process ID of the last run command, which is saved here as the variable PI, then sleeper is called with the process id of the gpg task (PI), and sleeper is also specified to output : instead of the default . every 3 seconds instead of the default 1. So a shorter version would be sleeper $!; The wait is also used here, though it may not be needed on your system. $ echo ">>> ENCRYPTING SQL BACKUP" $ gpg --output archive.tgz.asc --encrypt archive.tgz 1>/dev/null & $ PI=$!; sleeper $PI ":" 3; wait $PI && rm archive.tgz &>/dev/null Previously to get around the $! not always being available, I would instead check for the existance of the process ID by checking if the directory /proc/$PID existed, but not everyone uses proc anymore. That version is currently the one at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html but I plan on upgrading to this new version soon.

Update file with patch
diff originalfile updatedfile > my.patch

Delete all git branches except master
Delete all your branches except master (useful after archiving branches)

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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