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Reclaim standard in from the tty for a script that is in a pipeline
This will grab the controlling tty regardless of what STDOUT and STDERR are doing.

Display your ${PATH}, one directory per line
This works in bash and zsh. You may also want to alias it, if you need to look at it often... $ alias lpath="echo \$PATH | tr : \\\\n" "\$PATH" to make sure to look at your current $PATH

password generator
make password randomly, default 8 chars, using bash3.X only, no external program.

Display a block of text with AWK

Show a file in less without wrapping long lines

Delete line number 10 from file
Very useful when the ssh key of a host has changed and ssh refuses to connect to the machine, while giving you the line number that has changed in ~/.ssh/known_hosts.

ssh: change directory while connecting
Useful to create an alias that sends you right in the directory you want : alias server-etc="ssh -t server 'cd /etc && $SHELL'"

Split a large file, without wasting disk space
It's common to want to split up large files and the usual method is to use split(1). If you have a 10GiB file, you'll need 10GiB of free space. Then the OS has to read 10GiB and write 10GiB (usually on the same filesystem). This takes AGES. . The command uses a set of loop block devices to create fake chunks, but without making any changes to the file. This means the file splitting is nearly instantaneous. The example creates a 1GiB file, then splits it into 16 x 64MiB chunks (/dev/loop0 .. loop15). . Note: This isn't a drop-in replacement for using split. The results are block devices. tar and zip won't do what you expect when given block devices. . These commands will work: $ hexdump /dev/loop4 . $ gzip -9 < /dev/loop6 > part6.gz . $ cat /dev/loop10 > /media/usb/part10.bin

Matrix Style
Same as above but slooooow it down

Check syntax of all Perl modules or scripts underneath the current directory
Finds all *.p[ml]-files and runs a perl -c on them, checking whether Perl thinks they are syntactically correct


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