Commands by Karakh (2)

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Google URL shortener
Shorter and made into a function.

check open ports without netstat or lsof

find text in a file
this will find text in the directory you specify and give you line where it appears.

Perl one-liner to determine number of days since the Unix epoch
There are some environments that use this value for password and account expiration. It's helpful to be able to quickly determine the number of days since the Unix epoch (dse) when working directly with the configuration files as an administrator.

Post a message to another users screen via SSH
Post a message on another users screen via SSH

Mirror a directory structure from websites with an Apache-generated file indexes
wget/curl/friends are not good with mirroring files off websites, especially those with Apache-generated directory listings. These tools endlessly waste time downloading useless index HTML pages. lftp's mirror command does a better job without the mess.

Resize A Mounted EXT3 File System
Live extension of an ext3 file system on logical volume $v by 200GB without the need to unmount/remount. Requires that you have 1) a version of resize2fs that contains code merged from ext2online, and 2) kernel support for online resizing. (e.g. RHEL 5)

Give all those pictures the same name format, trailing zeros please for the right order, offset to merge different collections of pictures
When you have different digital cameras, different people, friends and you want to merge all those pictures together, then you get files with same names or files with 3 and 4 digit numbers etc. The result is a mess if you copy it together into one directory. But if you can add an offset to the picture number and set the number of leading zeros in the file name's number then you can manage. OFFS != 0 and LZ the same as the files currently have is not supported. Or left as an exercise, hoho ;) I love NF="${NF/#+(0)/}",it looks like a magic bash spell.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

remove newlines from specific lines in a file using sed


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