my previous version was wrong; this one is right

[unix-history] / usr / src / lib / libc / string / strerror.3

diff --git a/usr/src/lib/libc/string/strerror.3 b/usr/src/lib/libc/string/strerror.3
index 102a41d..daadbab 100644 (file)
--- a/usr/src/lib/libc/string/strerror.3
+++ b/usr/src/lib/libc/string/strerror.3
@@ -2,26 +2,32 @@
 .\" All rights reserved.  The Berkeley software License Agreement
 .\" specifies the terms and conditions for redistribution.
 .\"
 .\" All rights reserved.  The Berkeley software License Agreement
 .\" specifies the terms and conditions for redistribution.
 .\"

-.\"    @(#)strerror.3  6.2 (Berkeley) %G%
+.\"    @(#)strerror.3  6.6 (Berkeley) %G%

 .\"
 .\"

-.TH PERROR 3  ""
+.TH STRERROR 3  ""

 .UC 4
 .SH NAME
 .UC 4
 .SH NAME

-perror, sys_errlist, sys_nerr \- system error messages
+perror, strerror, sys_errlist, sys_nerr \- system error messages

 .SH SYNOPSIS
 .nf
 .SH SYNOPSIS
 .nf

-.B perror(string)
-.B char *string;
-.PP
-.B int sys_nerr;
-.B char *sys_errlist[];
+.ft B
+extern int errno, sys_nerr;
+extern char *sys_errlist[];
+
+#include <stdio.h>
+
+void perror(const char *string);
+
+char *strerror(int errnum);
+.ft R

 .fi
 .SH DESCRIPTION
 .I Perror
 produces a short error message on the standard error file
 describing the last error encountered during a call
 .fi
 .SH DESCRIPTION
 .I Perror
 produces a short error message on the standard error file
 describing the last error encountered during a call

-to the system from a C program.  If \fIstring\fP is non-NULL,
-it is printed, followed by a colon, followed by a space,
+to the system from a C program.  If
+.I string
+is non-NULL, it is printed, followed by a colon, followed by a space,

 followed by the message and a new-line.  Otherwise, just the
 message and the new-line are printed.  Most usefully, the argument
 string is the name of the program which incurred the error.
 followed by the message and a new-line.  Otherwise, just the
 message and the new-line are printed.  Most usefully, the argument
 string is the name of the program which incurred the error.


@@ -32,16 +38,19 @@ The error number is taken from the external variable
 which is set when errors occur but not cleared when
 non-erroneous calls are made.
 .PP
 which is set when errors occur but not cleared when
 non-erroneous calls are made.
 .PP

-To simplify variant formatting of messages, the vector of message strings
-.I sys_errlist
-is provided;
-.I errno
-can be used as an index in this table to get the
-message string without the newline.
+To simplify variant formatting of messages, the
+.I strerror
+function returns a pointer to the error message string mapped
+to the error number
+.IR errnum .
+.PP
+The message strings can be accessed directly using the external
+character array
+.IR sys_errlist .

 .I Sys_nerr
 .I Sys_nerr

-is the number of messages provided for in the table;
-it should be checked because new error codes may be added to the system before
-they are added to the table.
+is the total number of messages in the array.
+The use of these variables is deprecated;
+.I strerror
+should be used instead.

 .SH "SEE ALSO"
 .SH "SEE ALSO"

-intro(2),
-psignal(3)
+intro(2), psignal(3)