From 58f0484fa251c266ede97b591b499fe3dd4f578e Mon Sep 17 00:00:00 2001 From: "Rodney W. Grimes" Date: Fri, 27 May 1994 05:00:24 +0000 Subject: BSD 4.4 Lite Lib Sources --- lib/libc/string/strerror.3 | 124 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 lib/libc/string/strerror.3 (limited to 'lib/libc/string/strerror.3') diff --git a/lib/libc/string/strerror.3 b/lib/libc/string/strerror.3 new file mode 100644 index 000000000000..784c06168ada --- /dev/null +++ b/lib/libc/string/strerror.3 @@ -0,0 +1,124 @@ +.\" Copyright (c) 1980, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" This code is derived from software contributed to Berkeley by +.\" the American National Standards Committee X3, on Information +.\" Processing Systems. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)strerror.3 8.1 (Berkeley) 6/9/93 +.\" +.Dd June 9, 1993 +.Dt STRERROR 3 +.Os BSD 4 +.Sh NAME +.Nm perror , +.Nm strerror , +.Nm sys_errlist , +.Nm sys_nerr +.Nd system error messages +.Sh SYNOPSIS +.Fd #include +.Ft void +.Fn perror "const char *string" +.Vt extern char *sys_errlist[]; +.Vt extern int sys_nerr; +.Fd #include +.Ft char * +.Fn strerror "int errnum" +.Sh DESCRIPTION +The +.Fn strerror +and +.Fn perror +functions look up the error message string corresponding to an +error number. +.Pp +The +.Fn strerror +function accepts an error number argument +.Fa errnum +and +returns a pointer to the corresponding +message string. +.Pp +The +.Fn perror +function finds the error message corresponding to the current +value of the global variable +.Va errno +.Pq Xr intro 2 +and writes it, followed by a newline, to the +standard error file descriptor. +If the argument +.Fa string +is +.Pf non- Dv NULL , +it is prepended to the message +string and separated from it by +a colon and space +.Pq Ql \&:\ \& . +If +.Fa string +is +.Dv NULL , +only the error message string is printed. +.Pp +If +.Fa errnum +is not a recognized error number, +the error message string will contain +.Dq Li "Unknown error:\0 +followed by the error number in decimal. +.Pp +The message strings can be accessed directly using the external +array +.Fa sys_errlist . +The external value +.Fa sys_nerr +contains a count of the messages in +.Fa sys_errlist . +The use of these variables is deprecated; +.Fn strerror +should be used instead. +.Sh SEE ALSO +.Xr intro 2 , +.Xr psignal 3 +.Sh HISTORY +The +.Fn strerror +and +.Fn perror +functions first appeared in 4.4BSD. +.Sh BUGS +For unknown error numbers, the +.Fn strerror +function will return its result in a static buffer which +may be overwritten by subsequent calls. -- cgit v1.2.3