Commands by titan2x (3)

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Remount an already-mounted filesystem without unmounting it
Necessary for fsck for example. The remount functionality follows the standard way how the mount command works with options from fstab. It means the mount command doesn't read fstab (or mtab) only when a device and dir are fully specified. After this call all old mount options are replaced and arbitrary stuff from fstab is ignored, except the loop= option which is internally generated and maintained by the mount command. It does not change device or mount point.

clean up syntax and de-obfuscate perl script
the command show can be run in vim, here is the same thing on the command line $ cat script.pl | perl -MO=Deparse | perltidy

Show used disk space:

Create new user with home dir and given password
The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found. from http://en.wikipedia.org/wiki/Crypt_(Unix)

View Processeses like a fu, fu
Shows a less detailed output, made only of the process tree and their pids.

Install a local RPM package from your desktop, then use the YUM repository to resolve its dependencies.
When downloading RPMs from the Internet, you don't have to 'rpm -i' or 'rpm -U' to install the package. Especially, if the package has dependencies. If you have YUM setup to access an RPM repository, this command will install the downloaded package, then any dependencies through YUM that it relies on. Very handy on RPM-based systems.

Syntax Highlight your Perl code
This uses Text::Highlight to output the specified Perl file with syntax highlighting. A better alternative is my App::perlhl - find it on the CPAN: http://p3rl.org/App::perlhl

lists files and folders in a folder
lists files and folders in a folder with summary.

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"

Download a file securely via a remote SSH server
This command will download $file via server. I've used this when FTP was broken at the office and I needed to download some software packages.


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