diff options
Diffstat (limited to 'doc/fileevent.n')
| -rw-r--r-- | doc/fileevent.n | 41 |
1 files changed, 6 insertions, 35 deletions
diff --git a/doc/fileevent.n b/doc/fileevent.n index df48d2a..c1cea3a 100644 --- a/doc/fileevent.n +++ b/doc/fileevent.n @@ -1,13 +1,12 @@ '\" '\" Copyright (c) 1994 The Regents of the University of California. '\" Copyright (c) 1994-1996 Sun Microsystems, Inc. -'\" Copyright (c) 2008 Pat Thoyts '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" -.so man.macros .TH fileevent n 7.5 Tcl "Tcl Built-In Commands" +.so man.macros .BS '\" Note: do not modify the .SH NAME line immediately below! .SH NAME @@ -91,11 +90,6 @@ In nonblocking mode \fBputs\fR, \fBread\fR, and \fBgets\fR never block. See the documentation for the individual commands for information on how they handle blocking and nonblocking channels. .PP -Testing for the end of file condition should be done after any attempts -read the channel data. The eof flag is set once an attempt to read the -end of data has occurred and testing before this read will require an -additional event to be fired. -.PP The script for a file event is executed at global level (outside the context of any Tcl procedure) in the interpreter in which the \fBfileevent\fR command was invoked. @@ -105,49 +99,26 @@ In addition, the file event handler is deleted if it ever returns an error; this is done in order to prevent infinite loops due to buggy handlers. .SH EXAMPLE -.PP In this setup \fBGetData\fR will be called with the channel as an -argument whenever $chan becomes readable. The \fBread\fR call will -read whatever binary data is currently available without blocking. -Here the channel has the fileevent removed when an end of file -occurs to avoid being continually called (see above). Alternatively -the channel may be closed on this condition. -.PP +argument whenever $chan becomes readable. .CS proc GetData {chan} { - set data [read $chan] - puts "[string length $data] $data" - if {[eof $chan]} { - fileevent $chan readable {} + if {![eof $chan]} { + puts [gets $chan] } } -fconfigure $chan -blocking 0 -encoding binary \fBfileevent\fR $chan readable [list GetData $chan] .CE -.PP -The next example demonstrates use of \fBgets\fR to read line-oriented -data. -.PP -.CS -proc GetData {chan} { - if {[gets $chan line] >= 0} { - puts $line - } - if {[eof $chan]} { - close $chan - } -} -fconfigure $chan -blocking 0 -buffering line -translation crlf -\fBfileevent\fR $chan readable [list GetData $chan] -.CE .SH CREDITS .PP \fBfileevent\fR is based on the \fBaddinput\fR command created by Mark Diekhans. + .SH "SEE ALSO" fconfigure(n), gets(n), interp(n), puts(n), read(n), Tcl_StandardChannels(3) + .SH KEYWORDS asynchronous I/O, blocking, channel, event handler, nonblocking, readable, script, writable. |