The combination of ps and the grep command
 

Hi,

Could anyone tell me what the following command does in linux.

"ps -efww|grep vnc"

Thanks in advance.

Regards
Sujatha.

Have you looked up the man page for both commands? It seems fairly straight forward.

• ps displays the process table.
• -efww is a group of options which affect how the process table is displayed. Read about them in the man page.
• | causes the standard output stream of ps to be piped into the following command's standard input stream
• grep selects lines from the input stream which match a regular expression and prints them.
• vnc is a regular expression which matches the exact text vnc anywhere in the input stream.

So what I think this pipeline does is print a list of all vnc processes. I didn't look up the -efww part though, so you may want to check up on it.

HTH