Tcl Source Code

.PP
If the encoding profile \fBstrict\fR is in effect for the channel, the command
will raise an exception with the POSIX error code \fBEILSEQ\fR if any encoding
errors are encountered in the channel input data. The file pointer remains
unchanged and it is possible to introspect, and in some cases recover, by
changing the encoding in use. See \fBENCODING ERROR EXAMPLES\fR later.
.RE
.\" METHOD: isbinary
.TP
\fBchan isbinary \fIchannel\fR
.
Test whether the channel called \fIchannel\fR is a binary channel,
returning 1 if it is and, and 0 otherwise. A binary channel is
a channel with iso8859-1 encoding, -eofchar set to {} and
-translation set to cr.
.\" METHOD: names
.TP
\fBchan names\fR ?\fIpattern\fR?
.
Produces a list of all channel names. If \fIpattern\fR is specified,
only those channel names that match it (according to the rules of
\fBstring match\fR) will be returned.

    if (direction == TCL_READABLE) {
	ResetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
    }

    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * TclChanIsBinary --
 *
 *	Returns 1 if the channel is a binary channel, 0 otherwise.
 *
 * Results:
 *	1 or 0, always.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclChanIsBinary(
    Tcl_Channel chan)		/* Does this channel have EOF? */
{
    ChannelState *statePtr = ((Channel *) chan)->state;
				/* State of real channel structure. */

    return ((statePtr->encoding == GetBinaryEncoding()) && !statePtr->inEofChar
	    && (!GotFlag(statePtr, TCL_READABLE) || (statePtr->inputTranslation == TCL_TRANSLATE_LF))
	    && (!GotFlag(statePtr, TCL_WRITABLE) || (statePtr->outputTranslation == TCL_TRANSLATE_LF)));
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_Eof --
 *
 *	Returns 1 if the channel is at EOF, 0 otherwise.
 *

    if (TclGetChannelFromObj(interp, objv[1], &chan, NULL, 0) != TCL_OK) {
	return TCL_ERROR;
    }

    Tcl_SetObjResult(interp, Tcl_NewBooleanObj(Tcl_Eof(chan)));
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * ChanIsBinaryCmd --
 *
 *	This function is invoked to process the Tcl "chan isbinary" command. See the
 *	user documentation for details on what it does.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	Sets interp's result to boolean true or false depending on whether the
 *	specified channel is a binary channel.
 *
 *---------------------------------------------------------------------------
 */

static int
ChanIsBinaryCmd(
    TCL_UNUSED(void *),
    Tcl_Interp *interp,		/* Current interpreter. */
    int objc,			/* Number of arguments. */
    Tcl_Obj *const objv[])	/* Argument objects. */
{
    Tcl_Channel chan;

    if (objc != 2) {
	Tcl_WrongNumArgs(interp, 1, objv, "channel");
	return TCL_ERROR;
    }

    if (TclGetChannelFromObj(interp, objv[1], &chan, NULL, 0) != TCL_OK) {
	return TCL_ERROR;
    }

    Tcl_SetObjResult(interp, Tcl_NewBooleanObj(TclChanIsBinary(chan)));
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_ExecObjCmd --
 *
 *	This function is invoked to process the "exec" Tcl command. See the

	{"close",	Tcl_CloseObjCmd,	TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
	{"copy",	Tcl_FcopyObjCmd,	NULL, NULL, NULL, 0},
	{"create",	TclChanCreateObjCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},		/* TIP #219 */
	{"eof",		Tcl_EofObjCmd,		TclCompileBasic1ArgCmd, NULL, NULL, 0},
	{"event",	Tcl_FileEventObjCmd,	TclCompileBasic2Or3ArgCmd, NULL, NULL, 0},
	{"flush",	Tcl_FlushObjCmd,	TclCompileBasic1ArgCmd, NULL, NULL, 0},
	{"gets",	Tcl_GetsObjCmd,		TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
	{"isbinary",ChanIsBinaryCmd,		TclCompileBasic1ArgCmd, NULL, NULL, 0},
	{"names",	TclChannelNamesCmd,	TclCompileBasic0Or1ArgCmd, NULL, NULL, 0},
	{"pending",	ChanPendingObjCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},		/* TIP #287 */
	{"pipe",	ChanPipeObjCmd,		TclCompileBasic0ArgCmd, NULL, NULL, 0},		/* TIP #304 */
	{"pop",		TclChanPopObjCmd,	TclCompileBasic1ArgCmd, NULL, NULL, 0},		/* TIP #230 */
	{"postevent",	TclChanPostEventObjCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},	/* TIP #219 */
	{"push",	TclChanPushObjCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},		/* TIP #230 */
	{"puts",	Tcl_PutsObjCmd,		NULL, NULL, NULL, 0},

MODULE_SCOPE int	TclChannelGetBlockingMode(Tcl_Channel chan);
MODULE_SCOPE int	TclCheckArrayTraces(Tcl_Interp *interp, Var *varPtr,
			    Var *arrayPtr, Tcl_Obj *name, int index);
MODULE_SCOPE int	TclCheckEmptyString(Tcl_Obj *objPtr);
MODULE_SCOPE int	TclChanCaughtErrorBypass(Tcl_Interp *interp,
			    Tcl_Channel chan);
MODULE_SCOPE Tcl_ObjCmdProc TclChannelNamesCmd;
MODULE_SCOPE int TclChanIsBinary(Tcl_Channel chan);
MODULE_SCOPE Tcl_NRPostProc TclClearRootEnsemble;
MODULE_SCOPE int	TclCompareTwoNumbers(Tcl_Obj *valuePtr,
			    Tcl_Obj *value2Ptr);
MODULE_SCOPE ContLineLoc *TclContinuationsEnter(Tcl_Obj *objPtr, Tcl_Size num,
			    Tcl_Size *loc);
MODULE_SCOPE void	TclContinuationsEnterDerived(Tcl_Obj *objPtr,
			    Tcl_Size start, Tcl_Size *clNext);

} -body {
    seek $f 0
    puts -nonewline $f 12345
    seek $f 0
    chan truncate $f 2
    read $f
} -result 12 -cleanup {
    catch {close $f}
    catch {removeFile $file}
}
test chan-15.3 {chan command: isbinary subcommand} -setup {
    set file [makeFile {} testIsBinary]
    set f [open $file w+]
    fconfigure $f -translation binary
} -body {
    chan isbinary $f
} -result 1 -cleanup {
    catch {close $f}
    catch {removeFile $file}
}

# TIP 287: chan pending
test chan-16.1 {chan command: pending subcommand} -body {
    chan pending