piping |

jezz · 05-03-2008, 09:06 PM

Can some one please give me an example of how it works as well as a description thank you

btmiller · 05-03-2008, 09:10 PM

Piping is simply the act of passing the standard output (usually printed in the terminal) of one program as standard input to another program, e.g.:

Code:

ls -l | less

pipes the output of ls -l to less so you can scroll through it, e.g. when listing a directory with lots of files.

Another example:

Code:

echo "The cat climbed the tree" | sed -e 's/cat/dog/'

prints "The dog climbed the tree" since the echo output is passed as input to sed.

konsolebox · 05-04-2008, 04:28 AM

a pipe is actually treated the same as a file but is always accessed by two processes and is a stream of memory (perhaps virtually) that loops itself to the beginning after reaching data to the end.. going back and forth for every read and write.

the write pointer always goes ahead before the read pointer..