hash(1)hash(1)NAMEhash - Remembers or reports utility locations
SYNOPSIShash [utility]
hash-r
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
hash: XCU5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
OPTIONS
Forgets all previously remembered utility locations.
OPERANDS
The name of a utility to be searched for and added to the list of
remembered locations. If utility contains one or more slashes, the
results are unspecified.
DESCRIPTION
The hash utility affects the way the current shell environment remem‐
bers the locations of utilities found. Depending on the arguments spec‐
ified, it adds utility locations to its list of remembered locations or
it purges the contents of the list.
When no arguments are specified, hash reports on the contents of the
list. This list consists of those utilities named in previous hash
invocations that have been invoked, and those invoked and found through
the normal command search process. This list includes the path name of
each utility in the list of remembered locations for the current shell
environment.
NOTES
The use of hash with utility names is unnecessary for most applica‐
tions, but may provide a performance improvement. The effects of hash-r can also be achieved by resetting the value of PATH.
RESTRICTIONS
If hash is called in a separate utility execution environment, such as
one of the following it will not affect the command search process of
the caller's environment. nohup hash-r find . -type f | xargs hash
Utilities provided as built-ins to the shell are not reported by hash.
EXIT STATUS
The following exit values are returned: Successful completion. An
error occurred.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of hash: Pro‐
vides a default value for the internationalization variables that are
unset or null. If LANG is unset or null, the corresponding value from
the default locale is used. If any of the internationalization vari‐
ables contains an invalid setting, the utility behaves as if none of
the variables had been defined. If set to a non-empty string value,
overrides the values of all the other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to multi‐
byte characters in arguments). Determines the locale that should be
used to affect the format and contents of diagnostic messages written
to standard error. Determines the location of message catalogues for
the processing of LC_MESSAGES. Determines the location of name.
SEE ALSO
Commands: command(1), type(1)
Standards: standards(5)hash(1)