Commands by unixmonkey6754 (3)

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Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

du and sort to find the biggest directories in defined filesystem
I had the problem that our monitoring showed that the "/" filesystem is >90% full. This command helped me to find out fast which subdirs are the biggest. The system has many NFS-mounts therefore the -x.

An alarm clock using xmms2 and at
Nice little alarm clock to wake you up on time (hopefully). You can also do 'echo "vlc path/to/song" | at 6:00

pretend to be busy in office to enjoy a cup of coffee
using seq inside a subshell instead of a bash sequence to create increments.

Write on the console without being registered
just use a space to prevent commands from being recorded in bash's history on most systems

Given process ID print its environment variables
Same as previous but compatible with BSD/IPSO

Find out current working directory of a process

Using bash inline
There are two ways to use "here documents" with bash to fill stdin: The following example shows use with the "bc" command. a) Using a delimiter at the end of data: $ less-than less-than eeooff bc > k=1024 > m=k*k > g=k*m > g > eeooff 1073741824 b) using the "inline" verion with three less-than symbols: $ less-than less-than less-than "k=1024; m=k*k; g=k*m; g" bc 1073741824 One nice advantage of using the triple less-than version is that the command can easily be recalled from command line history and re-executed. PS: in this "description", I had to use the name "less-than" to represent the less-than symbol because the commandlinefu input text box seems to eat up the real less-than symbols. Odd.

Two command output
Summarize established connections after netstat output. Using tee and /dev/stderr you can send one command output to terminal before executing wc so you can summarize at the bottom of the output.


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