basename - return the last component of a pathname

PROLOG  NAME  SYNOPSIS  DESCRIPTION  RETURN VALUE  ERRORS  EXAMPLES  Using basename()  Sample Input and Output Strings for the basename() and dirname() Functionsand the basename and dirname Utilities  RATIONALENone.FUTURE DIRECTIONSNone.SEE ALSOdirname()TheBaseDefinitionsvolumeofPOSIX.1-2017,<libgen.h>TheShellandUtilitiesvolumeofPOSIX.1-2017,basenameCOPYRIGHTPortionsofthistextarereprintedandreproducedinelectronicformfromIEEEStd1003.1-2017,StandardforInformationTechnology--PortableOperatingSystemInterface(POSIX),TheOpenGroupBaseSpecificationsIssue7,2018Edition,Copyright(C)2018bytheInstituteofElectricalandElectronicsEngineers,IncandTheOpenGroup.IntheeventofanydiscrepancybetweenthisversionandtheoriginalIEEEandTheOpenGroupStandard,theoriginalIEEEandTheOpenGroupStandardistherefereedocument.TheoriginalStandardcanbeobtainedonlineathttp://www.opengroup.org/unix/online.html.Anytypographicalorformattingerrorsthatappearinthispagearemostlikelytohavebeenintroducedduringtheconversionofthesourcefilestomanpageformat.Toreportsucherrors,seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html. 

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PROLOG

This manual page is part of the POSIX Programmer’s Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

basename — return the last component of a pathname

SYNOPSIS

#include <libgen.h>

char *basename(char *path);

DESCRIPTION

The basename() function shall take the pathname pointed to by path and return a pointer to the final component of the pathname, deleting any trailing ’/’ characters.

If the string pointed to by path consists entirely of the ’/’ character, basename() shall return a pointer to the string "/". If the string pointed to by path is exactly "//", it is implementation-defined whether ’/’ or "//" is returned.

If path is a null pointer or points to an empty string, basename() shall return a pointer to the string ".".

The basename() function may modify the string pointed to by path, and may return a pointer to internal storage. The returned pointer might be invalidated or the storage might be overwritten by a subsequent call to basename(). The returned pointer might also be invalidated if the calling thread is terminated.

The basename() function need not be thread-safe.

RETURN VALUE

The basename() function shall return a pointer to the final component of path.

ERRORS

No errors are defined.

The following sections are informative.

EXAMPLES

Using basename()

The following program fragment returns a pointer to the value lib, which is the base name of /usr/lib.

#include <libgen.h>
...
char name[] = "/usr/lib";
char *base;

base = basename(name);
...

Sample Input and Output Strings for the basename() and dirname() Functionsand the basename and dirname Utilities

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RATIONALENone.FUTURE DIRECTIONSNone.SEE ALSOdirname()TheBaseDefinitionsvolumeofPOSIX.1-2017,<libgen.h>TheShellandUtilitiesvolumeofPOSIX.1-2017,basenameCOPYRIGHTPortionsofthistextarereprintedandreproducedinelectronicformfromIEEEStd1003.1-2017,StandardforInformationTechnology--PortableOperatingSystemInterface(POSIX),TheOpenGroupBaseSpecificationsIssue7,2018Edition,Copyright(C)2018bytheInstituteofElectricalandElectronicsEngineers,IncandTheOpenGroup.IntheeventofanydiscrepancybetweenthisversionandtheoriginalIEEEandTheOpenGroupStandard,theoriginalIEEEandTheOpenGroupStandardistherefereedocument.TheoriginalStandardcanbeobtainedonlineathttp://www.opengroup.org/unix/online.html.Anytypographicalorformattingerrorsthatappearinthispagearemostlikelytohavebeenintroducedduringtheconversionofthesourcefilestomanpageformat.Toreportsucherrors,seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html.

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