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GETCWD(3)                BSD 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.  Otherwise a NULL pointer is
     returned and the global variable errno is set to indicate the error.  In addition, getwd() copies the
     error message associated 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 getcwd() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').  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.

BUGS
     The getwd() function does not do sufficient error checking and is not able to return very long, but
     valid, paths.  It is provided for compatibility.

BSD                            November 24, 1997                           BSD