'\"
'\" Copyright (c) 1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH Tcl_SetErrno 3 8.3 Tcl "Tcl Library Procedures"
.so man.macros
.BS
.SH NAME
Tcl_SetErrno, Tcl_GetErrno, Tcl_ErrnoId, Tcl_ErrnoMsg \- manipulate errno to store and retrieve error codes
Tcl_SetErrno, Tcl_GetErrno, Tcl_ErrnoId, Tcl_ErrnoMsg, Tcl_WinConvertError \- manipulate errno to store and retrieve error codes
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
\fBTcl_SetErrno\fR(\fIerrorCode\fR)
.sp
int
\fBTcl_GetErrno\fR()
.sp
const char *
\fBTcl_ErrnoId\fR()
.sp
const char *
\fBTcl_ErrnoMsg\fR(\fIerrorCode\fR)
.sp
void
\fBTcl_WinConvertError\fR(\fIwinErrorCode\fR)
.fi
.SH ARGUMENTS
.AS int errorCode
.AP int errorCode in
A POSIX error code such as \fBENOENT\fR.
.AS unsigned int winErrorCode in
.AP DWORD winErrorCode in
A Windows or Winsock error code such as \fBERROR_FILE_NOT_FOUND\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.

\fBTcl_ErrnoMsg\fR returns a human-readable string such as
.QW "permission denied"
that corresponds to the value of its
\fIerrorCode\fR argument.  The \fIerrorCode\fR argument is
typically the value returned by \fBTcl_GetErrno\fR.
The strings returned by these functions are
statically allocated and the caller must not free or modify them.
.PP
\fBTcl_WinConvertError\fR (Windows only) maps the passed Windows or Winsock
error code to a POSIX error and stores it in \fBerrno\fR.

.SH KEYWORDS
errno, error code, global variables

        close $sock
	removeFile script
    } -result {{} ok}
test socket-14.11.0 {pending [socket -async] and nonblocking [puts], no listener, no flush} \
    -constraints {socket notWinCI} \
    -body {
        set sock [socket -async localhost [randport]]
        fileevent $sock writable {incr x}
        vwait x
        fconfigure $sock -blocking 0
        puts $sock ok
        fileevent $sock writable {set x 1}
        fileevent $sock writable {incr x}
        vwait x
        close $sock
    } -cleanup {
        catch {close $sock}
        unset x
    } -result {transport endpoint is not connected} -returnCodes 1
test socket-14.11.1 {pending [socket -async] and nonblocking [puts], no listener, flush} \