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Diffstat (limited to 'doc/close.n')
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diff --git a/doc/close.n b/doc/close.n new file mode 100644 index 0000000..4ee53ea --- /dev/null +++ b/doc/close.n @@ -0,0 +1,59 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +'\" SCCS: @(#) close.n 1.11 97/08/22 18:50:48 +'\" +.so man.macros +.TH close n 7.5 Tcl "Tcl Built-In Commands" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +close \- Close an open channel. +.SH SYNOPSIS +\fBclose \fIchannelId\fR +.BE + +.SH DESCRIPTION +.PP +Closes the channel given by \fIchannelId\fR. \fIChannelId\fR must be a +channel identifier such as the return value from a previous \fBopen\fR +or \fBsocket\fR command. +All buffered output is flushed to the channel's output device, +any buffered input is discarded, the underlying file or device is closed, +and \fIchannelId\fR becomes unavailable for use. +.VS "" br +.PP +If the channel is blocking, the command does not return until all output +is flushed. +If the channel is nonblocking and there is unflushed output, the +channel remains open and the command +returns immediately; output will be flushed in the background and the +channel will be closed when all the flushing is complete. +.VE +.PP +If \fIchannelId\fR is a blocking channel for a command pipeline then +\fBclose\fR waits for the child processes to complete. +.VS "" br +.PP +If the channel is shared between interpreters, then \fBclose\fR +makes \fIchannelId\fR unavailable in the invoking interpreter but has no +other effect until all of the sharing interpreters have closed the +channel. +When the last interpreter in which the channel is registered invokes +\fBclose\fR, the cleanup actions described above occur. See the +\fBinterp\fR command for a description of channel sharing. +.PP +Channels are automatically closed when an interpreter is destroyed and +when the process exits. Channels are switched to blocking mode, to ensure +that all output is correctly flushed before the process exits. +.VE +.PP +The command returns an empty string, and may generate an error if +an error occurs while flushing output. + +.SH KEYWORDS +blocking, channel, close, nonblocking |