1.\" Copyright (c) 1983, 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.\" @(#)scandir.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: src/lib/libc/gen/scandir.3,v 1.3.2.5 2003/03/15 15:11:05 trhodes Exp $ 34.\" 35.Dd November 4, 2010 36.Dt SCANDIR 3 37.Os 38.Sh NAME 39.Nm scandir , 40.Nm alphasort 41.Nd scan a directory 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In sys/types.h 46.In dirent.h 47.Ft int 48.Fn scandir "const char *dirname" "struct dirent ***namelist" "int \\*(lp*select\\*(rp\\*(lpconst struct dirent *\\*(rp" "int \\*(lp*compar\\*(rp\\*(lpconst struct dirent **, const struct dirent **\\*(rp" 49.Ft int 50.Fn alphasort "const struct dirent **d1" "const struct dirent **d2" 51.Sh DESCRIPTION 52The 53.Fn scandir 54function 55reads the directory 56.Fa dirname 57and builds an array of pointers to directory 58entries using 59.Xr malloc 3 . 60It returns the number of entries in the array. 61A pointer to the array of directory entries is stored in the location 62referenced by 63.Fa namelist . 64.Pp 65The 66.Fa select 67argument is a pointer to a user supplied subroutine which is called by 68.Fn scandir 69to select which entries are to be included in the array. 70The select routine is passed a 71pointer to a directory entry and should return a non-zero 72value if the directory entry is to be included in the array. 73If 74.Fa select 75is null, then all the directory entries will be included. 76.Pp 77The 78.Fa compar 79argument is a pointer to a user supplied subroutine which is passed to 80.Xr qsort 3 81to sort the completed array. 82If this pointer is null, the array is not sorted. 83.Pp 84The 85.Fn alphasort 86function 87is a routine which can be used for the 88.Fa compar 89argument to sort the array alphabetically. 90.Pp 91The memory allocated for the array can be deallocated with 92.Xr free 3 , 93by freeing each pointer in the array and then the array itself. 94.Sh DIAGNOSTICS 95Returns \-1 if the directory cannot be opened for reading or if 96.Xr malloc 3 97cannot allocate enough memory to hold all the data structures. 98.Sh SEE ALSO 99.Xr directory 3 , 100.Xr malloc 3 , 101.Xr qsort 3 , 102.Xr dir 5 103.Sh HISTORY 104The 105.Fn scandir 106and 107.Fn alphasort 108functions appeared in 109.Bx 4.2 . 110