Commands tagged parameter expansion (7)

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A random password generator

Install a LAMP server in a Debian based distribution
The execution of this command will install a LAMP server (Linux, Apache, MySQL and PHP) in a Debian based distribution. For example, in Ubuntu.

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

Print a row of 50 hyphens
This feels more intuitive to me.

Kill any lingering ssh processes
Also ignoring "sshd" server is necessary since you should not kill ssh server processes.

Clone or rescue a block device
If you use the logfile feature of ddrescue, the data is rescued very efficiently (only the needed blocks are read). Also you can interrupt the rescue at any time and resume it later at the same point. http://www.gnu.org/software/ddrescue/ddrescue.html

list files recursively by size

Jump to line X in file in Nano.
Starts the cursor on line X of file foo. Useful for longer files in which it takes a long time to scroll. If X is greater than the number of lines in file foo, it will go to the last existing line.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Command line progress bar
This command tar?s up a directory and sends the output to gzip, showing a rate of 223MB/s. This may require you installing the pv command. For debian based users out there: $ sudo aptitude install pv


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