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 38.Sh NAME 39.Nm getcwd , 40.Nm getwd 41.Nd get working directory pathname 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In unistd.h 46.Ft char * 47.Fn getcwd "char *buf" "size_t size" 48.Ft char * 49.Fn getwd "char *buf" 50.Sh DESCRIPTION 51The 52.Fn getcwd 53function copies the absolute pathname of the current working directory 54into the memory referenced by 55.Fa buf 56and returns a pointer to 57.Fa buf . 58The 59.Fa size 60argument is the size, in bytes, of the array referenced by 61.Fa buf . 62.Pp 63If 64.Fa buf 65is 66.Dv NULL , 67space is allocated as necessary to store the pathname. 68This space may later be 69.Xr free 3 Ns 'd . 70.Pp 71The function 72.Fn getwd 73is a compatibility routine which calls 74.Fn getcwd 75with its 76.Fa buf 77argument and a size of 78.Dv MAXPATHLEN 79(as defined in the include 80file 81.Aq Pa sys/param.h ) . 82Obviously, 83.Fa buf 84should be at least 85.Dv MAXPATHLEN 86bytes in length. 87.Pp 88These routines have traditionally been used by programs to save the 89name of a working directory for the purpose of returning to it. 90A much faster and less error-prone method of accomplishing this is to 91open the current directory 92.Pq Ql .\& 93and use the 94.Xr fchdir 2 95function to return. 96.Sh RETURN VALUES 97Upon successful completion, a pointer to the pathname is returned. 98Otherwise a 99.Dv NULL 100pointer is returned and the global variable 101.Va errno 102is set to indicate the error. 103In addition, 104.Fn getwd 105copies the error message associated with 106.Va errno 107into the memory referenced by 108.Fa buf . 109.Sh ERRORS 110The 111.Fn getcwd 112function 113will fail if: 114.Bl -tag -width Er 115.It Bq Er EACCES 116Read or search permission was denied for a component of the pathname. 117.It Bq Er EINVAL 118The 119.Fa size 120argument is zero. 121.It Bq Er ENOENT 122A component of the pathname no longer exists. 123.It Bq Er ENOMEM 124Insufficient memory is available. 125.It Bq Er ERANGE 126The 127.Fa size 128argument is greater than zero but smaller than the length of the pathname 129plus 1. 130.El 131.Sh SEE ALSO 132.Xr chdir 2 , 133.Xr fchdir 2 , 134.Xr malloc 3 , 135.Xr strerror 3 136.Sh STANDARDS 137The 138.Fn getcwd 139function 140conforms to 141.St -p1003.1-90 . 142The ability to specify a 143.Dv NULL 144pointer and have 145.Fn getcwd 146allocate memory as necessary is an extension. 147.Sh HISTORY 148The 149.Fn getwd 150function appeared in 151.Bx 4.0 . 152.Sh BUGS 153The 154.Fn getwd 155function 156does not do sufficient error checking and is not able to return very 157long, but valid, paths. 158It is provided for compatibility. 159