1.\" $NetBSD: scandir.3,v 1.4 1995/02/25 08:51:39 cgd Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)scandir.3 8.1 (Berkeley) 6/4/93 35.\" 36.Dd June 4, 1993 37.Dt SCANDIR 3 38.Os BSD 4.2 39.Sh NAME 40.Nm scandir , 41.Nm alphasort 42.Nd scan a directory 43.Sh SYNOPSIS 44.Fd #include <sys/types.h> 45.Fd #include <dirent.h> 46.Ft int 47.Fn scandir "const char *dirname" "struct dirent ***namelist" "int \\*(lp*select\\*(rp\\*(lpstruct dirent *\\*(rp" "int \\*(lp*compar\\*(rp\\*(lpconst void *, const void *\\*(rp" 48.Ft int 49.Fn alphasort "const void *d1" "const void *d2" 50.Sh DESCRIPTION 51The 52.Fn scandir 53function 54reads the directory 55.Fa dirname 56and builds an array of pointers to directory 57entries using 58.Xr malloc 3 . 59It returns the number of entries in the array. 60A pointer to the array of directory entries is stored in the location 61referenced by 62.Fa namelist . 63.Pp 64The 65.Fa select 66parameter is a pointer to a user supplied subroutine which is called by 67.Fn scandir 68to select which entries are to be included in the array. 69The select routine is passed a 70pointer to a directory entry and should return a non-zero 71value if the directory entry is to be included in the array. 72If 73.Fa select 74is null, then all the directory entries will be included. 75.Pp 76The 77.Fa compar 78parameter is a pointer to a user supplied subroutine which is passed to 79.Xr qsort 3 80to sort the completed array. 81If this pointer is null, the array is not sorted. 82.Pp 83The 84.Fn alphasort 85function 86is a routine which can be used for the 87.Fa compar 88parameter to sort the array alphabetically. 89.Pp 90The memory allocated for the array can be deallocated with 91.Xr free 3 , 92by freeing each pointer in the array and then the array itself. 93.Sh DIAGNOSTICS 94Returns \-1 if the directory cannot be opened for reading or if 95.Xr malloc 3 96cannot allocate enough memory to hold all the data structures. 97.Sh SEE ALSO 98.Xr directory 3 , 99.Xr malloc 3 , 100.Xr qsort 3 , 101.Xr dir 5 102.Sh HISTORY 103The 104.Fn scandir 105and 106.Fn alphasort 107functions appeared in 108.Bx 4.2 . 109