Command built-in

The command built-in executes a utility bypassing functions. This is useful when you want to execute a utility that has the same name as a function. The built-in also has options to search for the location of the utility.

Synopsis

command [-p] name [arguments…]

command -v|-V [-p] name

Description

Without the -v or -V option, the command built-in executes the utility specified by the name with the given arguments. This is similar to the execution of a simple command, but the functions are not searched for the name.

With the -v or -V option, the built-in identifies the type of the name and, optionally, the location of the utility. The -v option prints the pathname of the utility, if found, and the -V option prints a more detailed description of the utility.

Options

The -p (--path) option causes the built-in to search for the utility in the standard search path instead of the current PATH.

The -v (--identify) option identifies the type of the command name and prints the pathname of the utility, if found.

The -V (--verbose-identify) option identifies the type of the command name and prints a more detailed description of the utility.

Operands

The name operand specifies the name of the utility to execute or identify. The arguments are passed to the utility when executing it.

Standard output

When the -v option is given, the built-in prints the following:

• The absolute pathname of the utility, if found in the search path.
• The utility name itself, if it is a non-substitutive built-in, function, or reserved word, hence not subject to search.
• A command line that would redefine the alias, if the name is an alias.

When the -V option is given, the built-in describes the utility in a more descriptive, human-readable format. The exact format is not specified here as it is subject to change.

Nothing is printed if the utility is not found.

Errors

It is an error if the specified utility is not found or cannot be executed.

With the -v option, no error message is printed for the utility not found.

Exit status

Without the -v or -V option, the exit status is that of the utility executed. If the utility is not found, the exit status is 127. If the utility is found but cannot be executed, the exit status is 126.

With the -v or -V option, the exit status is 0 if the utility is found and 1 if not found.

Examples

See Replacing existing utilities.

Compatibility

POSIX requires that the name operand be specified, but many implementations allow it to be omitted, in which case the built-in does nothing.

When the utility is not found with the -v or -V option, some implementations return a non-zero exit status other than 1, especially 127.

When the utility is not found with the -V option, some implementations print an error message to the standard output while others to the standard error.