Commands by ivodeblasi (1)

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your terminal sings
you know the song... sing along

Massive change of file extension (bash)
Using bash parameters expansion

prevent large files from being cached in memory (backups!)
We all know... $ nice -n19 for low CPU priority.   $ ionice -c3 for low I/O priority.   nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.   http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache   To undo caching of a single file in hindsight, you can do $ cachedel   To check the cache status of a file, do $ cachestats

convert all files in a dir of a certain type to flv
This converts all m4a files in a dir to flv. You can just swap the m4a bit to anything else ffmpeg supports though, and it'll work.

Quickly analyse an Apache error log
This searches the Apache error_log for each of the 5 most significant Apache error levels, if any are found the date is then cut from the output in order to sort then print the most common occurrence of each error.

Show all the available information about your current distribution, package management and base
Just run this command and it will printout all the info available about your current distribution and package management system.

Sum columns from CSV column $COL

Print just line 4 from a textfile
this method should be the fastest

Output entire line once per unique value of the first column
Removes duplicates in the specified field/column while outputting entire lines. An elegant command for processing tab (or otherwise) delimited data.

detect partitions
`blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices. -c /dev/null - Do not use cached output from /etc/blkid.tab or /etc/blkid/blkid.tab (RHEL) -i - Display I/O Limits (aka I/O topology) information (not available in RHEL) -p - Low-level superblock probing mode (not available in RHEL)


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