Commands by ranjha (1)

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Download Youtube video with wget!
Nothing special required, just wget, sed & tr!

Check if a process is running
Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.

shush MOTD
I'm annoyed by the boilerplate "don't login unless you are supposed messages in our environment" - this shuts them up.

Print all fields in a file/output from field N to the end of the line

Backup files incremental with rsync to a NTFS-Partition
This will backup the _contents_ of /media/SOURCE to /media/TARGET where TARGET is formatted with ntfs. The --modify-window lets rsync ignore the less accurate timestamps of NTFS.

Functions to display, save and restore $IFS
You can display, save and restore the value of $IFS using conventional Bash commands, but these functions, which you can add to your ~/.bashrc file make it really easy. To display $IFS use the function ifs shown above. In the sample output, you can see that it displays the characters and their hexadecimal equivalent. This function saves it in a variable called $saveIFS: $ sifs () { saveIFS=$IFS; } Use this function to restore it $ rifs () { IFS=$saveIFS; } Add this line in your ~/.bashrc file to save a readonly copy of $IFS: $ declare -r roIFS=$IFS Use this function to restore that one to $IFS $ rrifs () { IFS=$roIFS; }

Setting reserved blocks percentage to 1%
According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition. http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/

Show an application's environment variables

scping files with streamlines compression (tar gzip)
it compresses the files and folders to stdout, secure copies it to the server's stdin and runs tar there to extract the input and output to whatever destination using -C. if you emit "-C /destination", it will extract it to the home folder of the user, much like `scp file [email protected]:`. the "v" in the tar command can be removed for no verbosity.

Rename files in batch


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