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authordkf <donal.k.fellows@manchester.ac.uk>2007-10-29 01:42:18 (GMT)
committerdkf <donal.k.fellows@manchester.ac.uk>2007-10-29 01:42:18 (GMT)
commit71f78ed1de764f208d95b703744c7682d448c3e3 (patch)
tree8e72d3dd4068fc22320de66ab7145fa75119f54c /doc/chan.n
parentccacc920f9cd610a9a9d8e800f623c20bf43a702 (diff)
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Next stage of doing GOOBE improvements to documentation now that the html generation works
Diffstat (limited to 'doc/chan.n')
-rw-r--r--doc/chan.n25
1 files changed, 17 insertions, 8 deletions
diff --git a/doc/chan.n b/doc/chan.n
index f2b6fe7..9580c64 100644
--- a/doc/chan.n
+++ b/doc/chan.n
@@ -4,7 +4,7 @@
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
-'\" RCS: @(#) $Id: chan.n,v 1.13 2007/10/26 20:11:52 dgp Exp $
+'\" RCS: @(#) $Id: chan.n,v 1.14 2007/10/29 01:42:18 dkf Exp $
.so man.macros
.TH chan n 8.5 Tcl "Tcl Built-In Commands"
.BS
@@ -293,7 +293,9 @@ Note that \fIinputChan\fR can become readable during a background
copy. You should turn off any \fBchan event\fR or \fBfileevent\fR
handlers during a background copy so those handlers do not interfere
with the copy. Any I/O attempted by a \fBchan event\fR or
-\fBfileevent\fR handler will get a "channel busy" error.
+\fBfileevent\fR handler will get a
+.QW "channel busy"
+error.
.PP
\fBChan copy\fR translates end-of-line sequences in \fIinputChan\fR
and \fIoutputChan\fR according to the \fB\-translation\fR option for
@@ -333,7 +335,11 @@ the channel.
.PP
The argument \fImode\fR specifies if the new channel is opened for
reading, writing, or both. It has to be a list containing any of the
-strings "\fBread\fR" or "\fBwrite\fR". The list must have at least one
+strings
+.QW \fBread\fR
+or
+.QW \fBwrite\fR .
+The list must have at least one
element, as a channel you can neither write to nor read from makes no
sense. The handler command for the new channel must support the chosen
mode, or an error is thrown.
@@ -411,9 +417,11 @@ while waiting for the data to arrive. If an application invokes
\fBchan gets\fR or \fBchan read\fR on a blocking channel when there is
no input data available, the process will block; until the input data
arrives, it will not be able to service other events, so it will
-appear to the user to ``freeze up''. With \fBchan event\fR, the
+appear to the user to
+.QW "freeze up" .
+With \fBchan event\fR, the
process can tell when data is present and only invoke \fBchan gets\fR
-or \fBchan read\fR when they won't block.
+or \fBchan read\fR when they will not block.
.PP
A channel is considered to be readable if there is unread data
available on the underlying device. A channel is also considered to
@@ -496,7 +504,8 @@ only those channel names that match it (according to the rules of
.TP
\fBchan pending \fImode channelId\fR
.
-Depending on whether \fImode\fR is "input" or "output", returns the number of
+Depending on whether \fImode\fR is \fBinput\fR or \fBoutput\fR,
+returns the number of
bytes of input or output (respectively) currently buffered
internally for \fIchannelId\fR (especially useful in a readable event
callback to impose application-specific limits on input line lengths to avoid
@@ -510,7 +519,7 @@ This subcommand is used by command handlers specified with \fBchan
create\fR. It notifies the channel represented by the handle
\fIchannelId\fR that the event(s) listed in the \fIeventSpec\fR have
occurred. The argument has to be a list containing any of the strings
-"\fBread\fR" and "\fBwrite\fR". The list must contain at least one
+\fBread\fR and \fBwrite\fR. The list must contain at least one
element as it does not make sense to invoke the command if there are
no events to post.
.RS
@@ -575,7 +584,7 @@ is possible for an arbitrarily large amount of data to be buffered for
a channel in nonblocking mode, which could consume a large amount of
memory. To avoid wasting memory, nonblocking I/O should normally be
used in an event-driven fashion with the \fBchan event\fR command
-(don't invoke \fBchan puts\fR unless you have recently been notified
+(do not invoke \fBchan puts\fR unless you have recently been notified
via a file event that the channel is ready for more output data).
.RE
.TP