whence command (displays how character strings would be interpreted if used as commands)

Organization of this page

Format
Description
Arguments
Return codes
Notes
Usage example

Format

whence  [-p] [-v] name  [name...]

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Description

This command displays how specified character strings would be interpreted if used as commands. When neither option is specified, the output is as follows.

If a specified character string is a command, the path name of the command is output.
If a specified character string is an alias, the value of the alias is output.
If a specified character string is a reserved word, standard shell command, extended shell command, or function, the specified character string is output.
If none of the above applies, nothing is output and the command terminates with a return code of 1.

If the -p and -v options are both specified, the whence command assumes that a specified character string is a command and produces output accordingly. If the name argument is omitted, the command terminates with an error and returns 1 as the return code.

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Arguments

-p

Specifies that the specified character strings are to be handled as commands whose paths are to be output.

-v

Specifies that whether each specified character string is a command, reserved-word, alias, standard shell command, extended shell command, or function is to be output.

The following table shows the contents of the output:

No.	Output contents	Meaning
`1`	`name` `is a reserved word`	`name` is a reserved word.
`2`	`name` `is a function`	`name` is a function.
`3`	`name` `is a traced function`	`name` is a function for which the trace mode is enabled. If the function is undefined and the trace mode is enabled for it, the contents shown in No. 4 are output.
`4`	`name` `is an undefined function`	`name` is an undefined function.
`5`	`name` `is an extended shell command`	`name` is an extended shell command.
`6`	`name` `is a shell builtin`	`name` is a built-in command.
`7`	`name` `is a special shell builtin`	`name` is a special built-in command.
`8`	`name` `is a shell builtin not supported`	`name` is a command that is not provided in JP1/Advanced Shell.
`9`	`name` `is` `path-name`	`name` is a command or executable file.
`10`	`name` `is an alias for` `'alias-value'`	`name` is an alias.
`11`	`name` `is an exported alias for 'alias-value'`	`name` is an exported alias.
`12`	`name` `not found`	`name` is not a command, reserved-word, alias, standard shell command, extended shell command, or function.

name

Specifies a character string to be interpreted as a command. If this argument is omitted, the command terminates with an error and returns 1 as the return code.

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Return codes

Return code	Meaning
`0`	Normal termination
`1`	Error termination. Or, one of specified character strings could not be found as a command.

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Notes

Even if the command syntax of this regular built-in command is incorrect, it does not exit the shell that is executing the command.

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Usage example

Assume that pwd is a command and output its path.

Contents of the job definition script
```
whence -p pwd
```
Contents of the STDOUT file of the execution job
```
********   JOB SCOPE STDOUT    ********
/bin/pwd
```

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