> /dev/null 2>&1

Sammy2ooo · 07-16-2003, 08:40 AM

Hi

Can someone tell me what this does?

>/dev/null 2>&1

i know what /dev/null and zero are for but what the hack does 2>&1 ??

Greets Sam

Pres · 07-16-2003, 09:17 AM

1> means redirect stdout and 2> means redirect stderr. This is a guess now but 2>&1 probably indicates direct stderr to stdout, and then flush the lot down /dev/null.

cnjohnson · 07-16-2003, 09:20 AM

The first part, "> /dev/null" means send standard output to the 'bit bucket" or in other words, throw it away.

The second part, "2>&1" means "redirect standard error (2) to the same place as standard outout (1.)

Standard input, standard output, and standard error all are give special "file handles" by the operating system: 0, 1, 2. If you know a little C (or C++) programming, this will make more sense.

Cheers--
Charles