which(1) manual page

The which utility takes a list of command names and searches the path for each executable file that would be run had these commands actually been invoked.

The following options are available:

-a

List all instances of executables found (instead of just the first one of each).

-s

No output, just return 0 if all of the executables are found, or 1 if some were not found.

Some shells may provide a builtin which command which is similar or identical to this utility. Consult the builtin(1) manual page.

“	I think Unix and snowflakes are the only two classes of objects in the universe in which no two instances ever match exactly.	”
— Noel Chiappa

Manual Pages — WHICH

NAME

CONTENTS

SYNOPSIS

DESCRIPTION

SEE ALSO

HISTORY

AUTHORS

-a
	List all instances of executables found (instead of just the first one of each).
-s
	No output, just return 0 if all of the executables are found, or 1 if some were not found.