diff options
Diffstat (limited to 'doc/GetStdChan.3')
| -rw-r--r-- | doc/GetStdChan.3 | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/doc/GetStdChan.3 b/doc/GetStdChan.3 index a7d9501..be0e79f 100644 --- a/doc/GetStdChan.3 +++ b/doc/GetStdChan.3 @@ -3,7 +3,7 @@ '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" +'\" .TH Tcl_GetStdChannel 3 7.5 Tcl "Tcl Library Procedures" .so man.macros .BS @@ -34,18 +34,18 @@ Tcl defines three special channels that are used by various I/O related commands if no other channels are specified. The standard input channel has a channel name of \fBstdin\fR and is used by \fBread\fR and \fBgets\fR. The standard output channel is named \fBstdout\fR and is used by -\fBputs\fR. The standard error channel is named \fBstderr\fR and is used for +\fBputs\fR. The standard error channel is named \fBstderr\fR and is used for reporting errors. In addition, the standard channels are inherited by any child processes created using \fBexec\fR or \fBopen\fR in the absence of any other redirections. .PP The standard channels are actually aliases for other normal channels. The current channel associated with a standard channel can be retrieved by calling -\fBTcl_GetStdChannel\fR with one of +\fBTcl_GetStdChannel\fR with one of \fBTCL_STDIN\fR, \fBTCL_STDOUT\fR, or \fBTCL_STDERR\fR as the \fItype\fR. The return value will be a valid channel, or NULL. .PP -A new channel can be set for the standard channel specified by \fItype\fR +A new channel can be set for the standard channel specified by \fItype\fR by calling \fBTcl_SetStdChannel\fR with a new channel or NULL in the \fIchannel\fR argument. If the specified channel is closed by a later call to \fBTcl_Close\fR, then the corresponding standard channel will automatically be @@ -53,16 +53,18 @@ set to NULL. .PP If a non-NULL value for \fIchannel\fR is passed to \fBTcl_SetStdChannel\fR, then that same value should be passed to \fBTcl_RegisterChannel\fR, like so: +.PP .CS Tcl_RegisterChannel(NULL, channel); .CE +.PP This is a workaround for a misfeature in \fBTcl_SetStdChannel\fR that it fails to do some reference counting housekeeping. This misfeature cannot be corrected without contradicting the assumptions of some existing code that calls \fBTcl_SetStdChannel\fR. .PP If \fBTcl_GetStdChannel\fR is called before \fBTcl_SetStdChannel\fR, Tcl will -construct a new channel to wrap the appropriate platform-specific standard +construct a new channel to wrap the appropriate platform-specific standard file handle. If \fBTcl_SetStdChannel\fR is called before \fBTcl_GetStdChannel\fR, then the default channel will not be created. .PP @@ -75,7 +77,7 @@ assigned starting with standard input, followed by standard output, with standard error being last. .PP See \fBTcl_StandardChannels\fR for a general treatise about standard -channels and the behaviour of the Tcl library with regard to them. +channels and the behavior of the Tcl library with regard to them. .SH "SEE ALSO" Tcl_Close(3), Tcl_CreateChannel(3), Tcl_Main(3), tclsh(1) |