command(1) — Commands
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.
FLAGS
-pPerforms the command search using a default value for PATH that is guaranteed to find all of the standard utilities.
-vWrites 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.
-VWrites 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.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of command:
LANGProvides 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_ALLIf set to a non-empty string value, overrides the values of all the other internationalization variables.
LC_CTYPEDetermines 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_MESSAGESDetermines the locale that should be used to affect the format and contents of diagnostic messages written to standard error.
NLSPATHDetermines the location of message catalogues for the processing of LC_MESSAGES.
PATHDetermines the search path used during the command search unless the -p flag is specified.
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 flags 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
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.
EXIT VALUES
When the -v or V flags are specified, command returns one of the following values.
0Successful completion
>0The command_name could not be found, or an error occurred.
If the -v or V flags are not specified, command returns one of the following values on error.
126The utility specified by command_name was found but could not be invoked.
127An 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.