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command(1)
NAME
command - Treats command arguments as simple commands
SYNOPSIS
command [-p] command_name [argument...]
command [-v|-V] command_name
The command command causes the shell to treat the arguments to command as
simple commands, and suppresses the default shell function lookup.
STANDARDS
Interfaces documented on this reference page conform to industry standards
as follows:
command: XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
OPTIONS
-p Performs the command search using a default value for PATH that is
guaranteed to find all of the standard utilities.
-v Writes a string to standard output that indicates the path name or
command to be used by the shell in the current shell execution
environment to invoke command_name.
-V Writes a string to standard output that indicates how the name given in
the command_name operand will be interpreted by the shell in the
current shell execution environment.
DESCRIPTION
The command command allows you to run the following commands:
· User-defined commands whose names correspond to shell built-in
commands.
· System commands whose names correspond to shell built-in commands.
The command_name argument specifies the name of a utility. The one or more
optional arguments to command_name specify strings treated as arguments to
the specified utility. It also provides information concerning how a
command name will be interpreted by the shell.
NOTES
[DIGITAL] If command_name is not the name of a function, the effect of
command is the same as would be obtained by specifying command_name without
command.
RESTRICTIONS
Since the -v and -V options to command produce output in relation to the
current shell execution environment, if command is called in a subshell or
separate utility execution environment, it may not produce correct results.
The following are examples of this type of operation:
(PATH=foo command -v)
nohup command -v
EXIT STATUS
When the -v or -V options are specified, command returns one of the
following values.
0 Successful completion.
>0 The command_name could not be found, or an error occurred.
If the -v or -V options are not specified, command returns one of the
following values on error.
126 The utility specified by command_name was found but could not be
invoked.
127 An error occurred in the command command, or the utility specified by
the command_name argument could not be invoked.
If no error occurs, the exit status of command is that of the command
specified by the arguments to command.
EXAMPLES
To ensure execution of the simple command pwd instead of the pwd shell
built-in command, enter the following:
command -p pwd
The preceding command displays the full path name of the current directory,
and does not perpetuate a view of the current directory location created by
links as the shell built-in command might do.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of command:
LANG
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
variables contains an invalid setting, the utility behaves as if none
of the variables had been defined.
LC_ALL
If set to a non-empty string value, overrides the values of all the
other internationalization variables.
LC_CTYPE
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).
LC_MESSAGES
Determines the locale that should be used to affect the format and
contents of diagnostic messages written to standard error.
NLSPATH
Determines the location of message catalogues for the processing of
LC_MESSAGES.
PATH
Determines the search path used during the command search unless the -p
option is specified.
SEE ALSO
Commands: env(1), hash(1), type(1)
Standards: standards(5)