hash (Unix)

hash
Developers	Various open-source and commercial developers
Operating system	Unix, Unix-like, IBM i
Type	Command

hash is a command on Unix and Unix-like operating systems that prints the location information for the commands found. The hash command has also been ported to the IBM i operating system.

Syntax

$ hash [name]

Description

When the user gives a command, the shell searches for the command in a list of locations specified by the PATH environmental variable. To avoid this work in future, when a command is found its location is stored in a hash table which is consulted before the search. The hash command is used to display or manipulate that hash table, particularly to replace obsolete entries in the rare but possible case that a command is added to the PATH. The hash command is built into the shell. The C shell implements this command in a different way.

Options

The following options are supported.

name

Searches the PATH environmental variable for the name given

Exit Status

This command returns the following exit values:

0

Successful completion

1

An Error occurred

Examples

$ hash

Print the hash table.

$ hash cat

Searches for command cat in the path specified by PATH environmental variable; if found, adds it to the hash.

See also

• find
• Unix shell
  • sh
  • bash
  • csh
  • ksh

External links

• hash – Shell and Utilities Reference, The Single UNIX Specification, Version 5 from The Open Group
• hash(1) – Solaris 11.4 User Commands Reference Manual