1.\" Copyright (c) 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.\" @(#)confstr.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd June 4, 1993 36.Dt CONFSTR 3 37.Os BSD 4 38.Sh NAME 39.Nm confstr 40.Nd get string-valued configurable variables 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.Fd #include <unistd.h> 45.Ft size_t 46.Fn confstr "int name" "char *buf" "size_t len" 47.Sh DESCRIPTION 48.Bf -symbolic 49This interface is obsoleted by 50.Xr sysctl 3 . 51.Ef 52.Pp 53The 54.Fn confstr 55function provides a method for applications to get configuration 56defined string values. 57.Pp 58The 59.Fa name 60argument specifies the system variable to be queried. 61Symbolic constants for each name value are found in the include file 62.Li <unistd.h> . 63The 64.Fa len 65argument specifies the size of the buffer referenced by the 66argument 67.Fa buf . 68If 69.Fa len 70is non-zero, 71.Fa buf 72is a non-null pointer, and 73.Fa name 74has a value, up to 75.Fa len 76\- 1 bytes of the value are copied into the buffer 77.Fa buf . 78The copied value is always null terminated. 79.Pp 80The available values are as follows: 81.Pp 82.Bl -tag -width "123456" 83.Pp 84.It Li _CS_PATH 85Return a value for the 86.Ev PATH 87environment variable that finds all the standard utilities. 88.El 89.Sh RETURN VALUES 90If the call to 91.Fn confstr 92is not successful, \-1 is returned and 93.Va errno 94is set appropriately. 95Otherwise, if the variable does not have a configuration defined value, 960 is returned and 97.Va errno 98is not modified. 99Otherwise, the buffer size needed to hold the entire configuration-defined 100value is returned. 101If this size is greater than the argument 102.Fa len , 103the string in 104.Fa buf 105was truncated. 106.Sh ERRORS 107The 108.Fn confstr 109function may fail and set 110.Va error 111for any of the errors specified for the library functions 112.Xr malloc 3 113and 114.Xr sysctl 3 . 115.Pp 116In addition, the following errors may be reported: 117.Bl -tag -width Er 118.It Bq Er EINVAL 119The value of the 120.Fa name 121argument is invalid. 122.Sh SEE ALSO 123.Xr sysctl 3 124.Sh HISTORY 125The 126.Fn confstr 127function first appeared in 128.Bx 4.4 . 129