1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)getcwd.3 8.2 (Berkeley) 12/11/93 33.\" $FreeBSD$ 34.\" 35.Dd November 24, 1997 36.Dt GETCWD 3 37.Os BSD 4.2 38.Sh NAME 39.Nm getcwd , 40.Nm getwd 41.Nd get working directory pathname 42.Sh SYNOPSIS 43.Fd #include <unistd.h> 44.Ft char * 45.Fn getcwd "char *buf" "size_t size" 46.Ft char * 47.Fn getwd "char *buf" 48.Sh DESCRIPTION 49The 50.Fn getcwd 51function copies the absolute pathname of the current working directory 52into the memory referenced by 53.Fa buf 54and returns a pointer to 55.Fa buf . 56The 57.Fa size 58argument is the size, in bytes, of the array referenced by 59.Fa buf . 60.Pp 61If 62.Fa buf 63is 64.Dv NULL , 65space is allocated as necessary to store the pathname. 66This space may later be 67.Xr free 3 Ns 'd. 68.Pp 69The function 70.Fn getwd 71is a compatibility routine which calls 72.Fn getcwd 73with its 74.Fa buf 75argument and a size of 76.Dv MAXPATHLEN 77(as defined in the include 78file 79.Aq Pa sys/param.h ) . 80Obviously, 81.Fa buf 82should be at least 83.Dv MAXPATHLEN 84bytes in length. 85.Pp 86These routines have traditionally been used by programs to save the 87name of a working directory for the purpose of returning to it. 88A much faster and less error-prone method of accomplishing this is to 89open the current directory 90.Pq Ql \&. 91and use the 92.Xr fchdir 2 93function to return. 94.Sh RETURN VALUES 95Upon successful completion, a pointer to the pathname is returned. 96Otherwise a 97.Dv NULL 98pointer is returned and the global variable 99.Va errno 100is set to indicate the error. 101In addition, 102.Fn getwd 103copies the error message associated with 104.Va errno 105into the memory referenced by 106.Fa buf . 107.Sh ERRORS 108The 109.Fn getcwd 110function 111will fail if: 112.Bl -tag -width [EACCES] 113.It Bq Er EACCES 114Read or search permission was denied for a component of the pathname. 115.It Bq Er EINVAL 116The 117.Fa size 118argument is zero. 119.It Bq Er ENOENT 120A component of the pathname no longer exists. 121.It Bq Er ENOMEM 122Insufficient memory is available. 123.It Bq Er ERANGE 124The 125.Fa size 126argument is greater than zero but smaller than the length of the pathname 127plus 1. 128.El 129.Sh SEE ALSO 130.Xr chdir 2 , 131.Xr fchdir 2 , 132.Xr malloc 3 , 133.Xr strerror 3 134.Sh STANDARDS 135The 136.Fn getcwd 137function 138conforms to 139.St -ansiC . 140The ability to specify a 141.Dv NULL 142pointer and have 143.Fn getcwd 144allocate memory as necessary is an extension. 145.Sh HISTORY 146The 147.Fn getwd 148function appeared in 149.Bx 4.0 . 150.Sh BUGS 151The 152.Fn getwd 153function 154does not do sufficient error checking and is not able to return very 155long, but valid, paths. 156It is provided for compatibility. 157