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GETCWD(3)	       FreeBSD Library Functions Manual		     GETCWD(3)

NAME
     getcwd, getwd -- get working directory pathname

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <unistd.h>

     char *
     getcwd(char *buf, size_t size);

     char *
     getwd(char	*buf);

DESCRIPTION
     The getcwd() function copies the absolute pathname	of the current working
     directory into the	memory referenced by buf and returns a pointer to buf.
     The size argument is the size, in bytes, of the array referenced by buf.

     If	buf is NULL, space is allocated	as necessary to	store the pathname.
     This space	may later be free(3)'d.

     The function getwd() is a compatibility routine which calls getcwd() with
     its buf argument and a size of MAXPATHLEN (as defined in the include file
     <sys/param.h>).  Obviously, buf should be at least	MAXPATHLEN bytes in
     length.

     These routines have traditionally been used by programs to	save the name
     of	a working directory for	the purpose of returning to it.	 A much	faster
     and less error-prone method of accomplishing this is to open the current
     directory (`.') and use the fchdir(2) function to return.

RETURN VALUES
     Upon successful completion, a pointer to the pathname is returned.	 Oth-
     erwise a NULL pointer is returned and the global variable errno is	set to
     indicate the error.  In addition, getwd() copies the error	message	asso-
     ciated with errno into the	memory referenced by buf.

ERRORS
     The getcwd() function will	fail if:

     [EACCES]		Read or	search permission was denied for a component
			of the pathname.

     [EINVAL]		The size argument is zero.

     [ENOENT]		A component of the pathname no longer exists.

     [ENOMEM]		Insufficient memory is available.

     [ERANGE]		The size argument is greater than zero but smaller
			than the length	of the pathname	plus 1.

SEE ALSO
     chdir(2), fchdir(2), malloc(3), strerror(3)

STANDARDS
     The getwd() and getcwd() functions	conform	to ISO/IEC 9945-1:1990
     ("POSIX.1").  The IEEE Std	1003.1-2004 ("POSIX.1")	revision marked
     getwd() as	legacy and recommended the use of getcwd() instead.  The IEEE
     Std 1003.1-2008 ("POSIX.1") revision removed getwd() from the specifica-
     tion.

     The ability to specify a NULL pointer and have getcwd() allocate memory
     as	necessary is an	extension.

HISTORY
     The getwd() function appeared in 4.0BSD.

SECURITY CONSIDERATIONS
     As	getwd()	does not know the length of the	supplied buffer, it is possi-
     ble for a long (but valid)	path to	overflow the buffer and	provide	a
     means for an attacker to exploit the caller.  getcwd() should be used in
     place of getwd() (the latter is only provided for compatibility pur-
     poses).

FreeBSD	13.0			April 29, 2010			  FreeBSD 13.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS | HISTORY | SECURITY CONSIDERATIONS

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