seterrno.3

linux系统下的音频通信

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'\" Copyright (c) 1996 Sun Microsystems, Inc.
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'\" SCCS: @(#) SetErrno.3 1.5 96/02/15 20:01:31
.so man.macros
.TH Tcl_SetErrno 3 7.5 Tcl "Tcl Library Procedures"
.BS
.SH NAME
Tcl_SetErrno, Tcl_GetErrno \- manipulate errno to store and retrieve error codes
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
void
\fBTcl_SetErrno\fR(\fIerrorCode\fR)
.sp
int
\fBTcl_GetErrno\fR()
.sp
.SH ARGUMENTS
.AS Tcl_Interp *errorCode in
.AP int errorCode in
A POSIX error code such as \fBENOENT\fR.
.BE

.SH DESCRIPTION
.PP
\fBTcl_SetErrno\fR and \fBTcl_GetErrno\fR provide portable access
to the \fBerrno\fR variable, which is used to record a POSIX error
code after system calls and other operations such as \fBTcl_Gets\fR.
These procedures are necessary because global variable accesses cannot
be made across module boundaries on some platforms.
.PP
\fBTcl_SetErrno\fR sets the \fBerrno\fR variable to the value of the
\fIerrorCode\fR argument
C procedures that wish to return error information to their callers
via \fBerrno\fR should call \fBTcl_SetErrno\fR rather than setting
\fBerrno\fR directly.
.PP
\fBTcl_GetErrno\fR returns the current value of \fBerrno\fR.
Procedures wishing to access \fBerrno\fR should call this procedure
instead of accessing \fBerrno\fR directly.

.SH KEYWORDS
errno, error code, global variables