diff options
Diffstat (limited to 'doc/CrtFileHdlr.3')
-rw-r--r-- | doc/CrtFileHdlr.3 | 184 |
1 files changed, 92 insertions, 92 deletions
diff --git a/doc/CrtFileHdlr.3 b/doc/CrtFileHdlr.3 index 9f504e6..27bd621 100644 --- a/doc/CrtFileHdlr.3 +++ b/doc/CrtFileHdlr.3 @@ -1,92 +1,92 @@ -'\" -'\" Copyright (c) 1990-1994 The Regents of the University of California. -'\" Copyright (c) 1994-1997 Sun Microsystems, Inc. -'\" -'\" See the file "license.terms" for information on usage and redistribution -'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" -'\" RCS: @(#) $Id: CrtFileHdlr.3,v 1.5 2005/05/10 18:33:54 kennykb Exp $ -'\" -.so man.macros -.TH Tcl_CreateFileHandler 3 8.0 Tcl "Tcl Library Procedures" -.BS -.SH NAME -Tcl_CreateFileHandler, Tcl_DeleteFileHandler \- associate procedure callbacks with files or devices (Unix only) -.SH SYNOPSIS -.nf -\fB#include <tcl.h>\fR -.sp -\fBTcl_CreateFileHandler\fR(\fIfd, mask, proc, clientData\fR) -.sp -\fBTcl_DeleteFileHandler\fR(\fIfd\fR) -.SH ARGUMENTS -.AS Tcl_FileProc clientData -.AP int fd in -Unix file descriptor for an open file or device. -.AP int mask in -Conditions under which \fIproc\fR should be called: -OR-ed combination of \fBTCL_READABLE\fR, \fBTCL_WRITABLE\fR, -and \fBTCL_EXCEPTION\fR. May be set to 0 to temporarily disable -a handler. -.AP Tcl_FileProc *proc in -Procedure to invoke whenever the file or device indicated -by \fIfile\fR meets the conditions specified by \fImask\fR. -.AP ClientData clientData in -Arbitrary one-word value to pass to \fIproc\fR. -.BE - -.SH DESCRIPTION -.PP -\fBTcl_CreateFileHandler\fR arranges for \fIproc\fR to be -invoked in the future whenever I/O becomes possible on a file -or an exceptional condition exists for the file. The file -is indicated by \fIfd\fR, and the conditions of interest -are indicated by \fImask\fR. For example, if \fImask\fR -is \fBTCL_READABLE\fR, \fIproc\fR will be called when -the file is readable. -The callback to \fIproc\fR is made by \fBTcl_DoOneEvent\fR, so -\fBTcl_CreateFileHandler\fR is only useful in programs that dispatch -events through \fBTcl_DoOneEvent\fR or through Tcl commands such -as \fBvwait\fR. -.PP -\fIProc\fR should have arguments and result that match the -type \fBTcl_FileProc\fR: -.CS -typedef void Tcl_FileProc( - ClientData \fIclientData\fR, - int \fImask\fR); -.CE -The \fIclientData\fR parameter to \fIproc\fR is a copy -of the \fIclientData\fR -argument given to \fBTcl_CreateFileHandler\fR when the callback -was created. Typically, \fIclientData\fR points to a data -structure containing application-specific information about -the file. \fIMask\fR is an integer mask indicating which -of the requested conditions actually exists for the file; it -will contain a subset of the bits in the \fImask\fR argument -to \fBTcl_CreateFileHandler\fR. -.PP -.PP -There may exist only one handler for a given file at a given time. -If \fBTcl_CreateFileHandler\fR is called when a handler already -exists for \fIfd\fR, then the new callback replaces the information -that was previously recorded. -.PP -\fBTcl_DeleteFileHandler\fR may be called to delete the -file handler for \fIfd\fR; if no handler exists for the -file given by \fIfd\fR then the procedure has no effect. -.PP -The purpose of file handlers is to enable an application to respond to -events while waiting for files to become ready for I/O. For this to work -correctly, the application may need to use non-blocking I/O operations on -the files for which handlers are declared. Otherwise the application may -block if it reads or writes too much data; while waiting for the I/O to -complete the application won't be able to service other events. Use -\fBTcl_SetChannelOption\fR with \fB\-blocking\fR to set the channel into -blocking or nonblocking mode as required. -.PP -Note that these interfaces are only supported by the Unix -implementation of the Tcl notifier. - -.SH KEYWORDS -callback, file, handler +'\"
+'\" Copyright (c) 1990-1994 The Regents of the University of California.
+'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\"
+'\" RCS: @(#) $Id: CrtFileHdlr.3,v 1.6 2007/10/28 14:17:38 dkf Exp $
+'\"
+.so man.macros
+.TH Tcl_CreateFileHandler 3 8.0 Tcl "Tcl Library Procedures"
+.BS
+.SH NAME
+Tcl_CreateFileHandler, Tcl_DeleteFileHandler \- associate procedure callbacks with files or devices (Unix only)
+.SH SYNOPSIS
+.nf
+\fB#include <tcl.h>\fR
+.sp
+\fBTcl_CreateFileHandler\fR(\fIfd, mask, proc, clientData\fR)
+.sp
+\fBTcl_DeleteFileHandler\fR(\fIfd\fR)
+.SH ARGUMENTS
+.AS Tcl_FileProc clientData
+.AP int fd in
+Unix file descriptor for an open file or device.
+.AP int mask in
+Conditions under which \fIproc\fR should be called:
+OR-ed combination of \fBTCL_READABLE\fR, \fBTCL_WRITABLE\fR,
+and \fBTCL_EXCEPTION\fR. May be set to 0 to temporarily disable
+a handler.
+.AP Tcl_FileProc *proc in
+Procedure to invoke whenever the file or device indicated
+by \fIfile\fR meets the conditions specified by \fImask\fR.
+.AP ClientData clientData in
+Arbitrary one-word value to pass to \fIproc\fR.
+.BE
+
+.SH DESCRIPTION
+.PP
+\fBTcl_CreateFileHandler\fR arranges for \fIproc\fR to be
+invoked in the future whenever I/O becomes possible on a file
+or an exceptional condition exists for the file. The file
+is indicated by \fIfd\fR, and the conditions of interest
+are indicated by \fImask\fR. For example, if \fImask\fR
+is \fBTCL_READABLE\fR, \fIproc\fR will be called when
+the file is readable.
+The callback to \fIproc\fR is made by \fBTcl_DoOneEvent\fR, so
+\fBTcl_CreateFileHandler\fR is only useful in programs that dispatch
+events through \fBTcl_DoOneEvent\fR or through Tcl commands such
+as \fBvwait\fR.
+.PP
+\fIProc\fR should have arguments and result that match the
+type \fBTcl_FileProc\fR:
+.CS
+typedef void Tcl_FileProc(
+ ClientData \fIclientData\fR,
+ int \fImask\fR);
+.CE
+The \fIclientData\fR parameter to \fIproc\fR is a copy
+of the \fIclientData\fR
+argument given to \fBTcl_CreateFileHandler\fR when the callback
+was created. Typically, \fIclientData\fR points to a data
+structure containing application-specific information about
+the file. \fIMask\fR is an integer mask indicating which
+of the requested conditions actually exists for the file; it
+will contain a subset of the bits in the \fImask\fR argument
+to \fBTcl_CreateFileHandler\fR.
+.PP
+.PP
+There may exist only one handler for a given file at a given time.
+If \fBTcl_CreateFileHandler\fR is called when a handler already
+exists for \fIfd\fR, then the new callback replaces the information
+that was previously recorded.
+.PP
+\fBTcl_DeleteFileHandler\fR may be called to delete the
+file handler for \fIfd\fR; if no handler exists for the
+file given by \fIfd\fR then the procedure has no effect.
+.PP
+The purpose of file handlers is to enable an application to respond to
+events while waiting for files to become ready for I/O. For this to work
+correctly, the application may need to use non-blocking I/O operations on
+the files for which handlers are declared. Otherwise the application may
+block if it reads or writes too much data; while waiting for the I/O to
+complete the application will not be able to service other events. Use
+\fBTcl_SetChannelOption\fR with \fB\-blocking\fR to set the channel into
+blocking or nonblocking mode as required.
+.PP
+Note that these interfaces are only supported by the Unix
+implementation of the Tcl notifier.
+
+.SH KEYWORDS
+callback, file, handler
|