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hash(1) [osf1 man page]

hash(1) 						      General Commands Manual							   hash(1)

NAME
hash - Remembers or reports utility locations SYNOPSIS
hash [utility] hash -r STANDARDS
Interfaces documented on this reference page conform to industry standards 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 remembers 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 applications, 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: Provides 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 multibyte 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)

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hash(1) 							   User Commands							   hash(1)

NAME
hash, rehash, unhash, hashstat - evaluate the internal hash table of the contents of directories SYNOPSIS
/usr/bin/hash [utility] /usr/bin/hash [-r] sh hash [-r] [name]... csh rehash unhash hashstat ksh hash [name]... hash [-r] DESCRIPTION
/usr/bin/hash The /usr/bin/hash utility affects the way the current shell environment remembers the locations of utilities found. Depending on the argu- ments specified, it adds utility locations to its list of remembered locations or it purges the contents of the list. When no arguments are specified, it reports on the contents of the list. The -r option causes the shell to forget all remembered locations. Utilities provided as built-ins to the shell are not reported by hash. sh For each name, the location in the search path of the command specified by name is determined and remembered by the shell. The -r option to the hash built-in causes the shell to forget all remembered locations. If no arguments are given, hash provides information about remem- bered commands. The Hits column of output is the number of times a command has been invoked by the shell process. The Cost column of output is a measure of the work required to locate a command in the search path. If a command is found in a "relative" directory in the search path, after changing to that directory, the stored location of that command is recalculated. Commands for which this will be done are indi- cated by an asterisk (*) adjacent to the Hits information. Cost will be incremented when the recalculation is done. csh rehash recomputes the internal hash table of the contents of directories listed in the path environmental variable to account for new com- mands added. unhash disables the internal hash table. hashstat prints a statistics line indicating how effective the internal hash table has been at locating commands (and avoiding execs). An exec is attempted for each component of the path where the hash function indicates a possible hit and in each component that does not begin with a '/'. ksh For each name, the location in the search path of the command specified by name is determined and remembered by the shell. The -r option to the hash built-in causes the shell to forget all remembered locations. If no arguments are given, hash provides information about remem- bered commands. OPERANDS
The following operand is supported by hash: utility The name of a utility to be searched for and added to the list of remembered locations. OUTPUT
The standard output of hash is used when no arguments are specified. Its format is unspecified, but includes the pathname of each utility in the list of remembered locations for the current shell environment. This list consists of those utilities named in previous hash invoca- tions that have been invoked, and may contain those invoked and found through the normal command search process. ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables that affect the execution of hash: LANG, LC_ALL, LC_CTYPE, LC_MES- SAGES, and NLSPATH. PATH Determine the location of utility. EXIT STATUS
The following exit values are returned by hash: 0 Successful completion. >0 An error occurred. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
csh(1), ksh(1), sh(1), attributes(5), environ(5), standards(5) SunOS 5.11 17 Jul 2002 hash(1)

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