Content-type: text/html Man page of basename

basename

Section: User Commands (1)
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NAME

basename, dirname - Returns the base file name or directory portion of a path name  

SYNOPSIS

basename string [suffix]

dirname string


 

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

basename:  XPG4, XPG4-UNIX

dirname:  XPG4, XPG4-UNIX

Refer to the standards(5) reference page for more information about industry standards and associated tags.
 

OPTIONS

None
 

OPERANDS

A string to be evaluated. This string may be empty. A file name suffix to be deleted if found. This operand applies to the basename command only, and is optional.
 

DESCRIPTION

The basename command reads the string specified on the command line, deletes the portion from the beginning to the last / (slash), and writes the base file name to standard output. If suffix is specified on the command line and suffix appears in string, the string is returned with the suffix removed.

The dirname command reads the string specified on the command line, deletes from the last / (slash) to the end of the line, and writes the remaining path name to standard output.

[Compaq]  The basename and dirname commands are generally used inside command substitutions within a shell procedure to specify an output file name that is some variation of a specified input file name. For more information, see the csh(1), ksh(1), and sh(1b) or sh(1p) reference pages.

The following table demonstrates the processing applied to characters with particular meanings by the basename and dirname commands.


basenamedirname
stringResultResult

///
////
/a/bb/a
//a//b//b//a
<null>err msgerr msg
aa.
"".
/aa/
/a/bb/a
a/bba


 

NOTES

It is not an error if suffix is not a part of string.
 

EXAMPLES

To display the base file name of a shell variable, enter: basename $WORKFILE

This displays the base file name of the value assigned to the WORKFILE shell variable. If WORKFILE is set to /u/gabe/program.c, then program.c is displayed. To construct, in a shell script, a file name that is the same as another file name, except for its suffix, enter the following command, using grave accents: OFILE=`basename $1 .c`.o
This assigns to OFILE the value of the first positional parameter ($1), but with its .c suffix changed to .o. If $1 is /u/jim/program.c, then OFILE becomes program.o. Because program.o is only a base file name, it identifies a file in the current directory.
The grave accents perform command substitution. To construct the name of a file located in the same directory as another, enter the following command, using grave accents: AOUTFILE=`dirname $TEXTFILE`/a.out
This sets the AOUTFILE shell variable to the name of an a.out file that is in the same directory as TEXTFILE. If TEXTFILE is /u/fran/prog.c, then the value of dirname $TEXTFILE is /u/fran and AOUTFILE becomes /u/fran/a.out.
 

ENVIRONMENT VARIABLES

The following environment variables affect the execution of basename and dirname: 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 contain 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 for the format and contents of diagnostic messages written to standard error. Determines the location of message catalogues for the processing of LC_MESSAGES.
 

SEE ALSO

Commands:  csh(1), ksh(1), Bourne shell sh(1b), POSIX shell sh(1p)

Standards:  standards(5)


 

Index

NAME
SYNOPSIS
STANDARDS
OPTIONS
OPERANDS
DESCRIPTION
NOTES
EXAMPLES
ENVIRONMENT VARIABLES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 02:42:44 GMT, October 02, 2010