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diff --git a/doc/dde.n b/doc/dde.n new file mode 100644 index 0000000..1df6c87 --- /dev/null +++ b/doc/dde.n @@ -0,0 +1,100 @@ +'\" +'\" Copyright (c) 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. +'\" +'\" SCCS: @(#) dde.n 1.3 98/01/28 12:48:08 +'\" +.so man.macros +.TH dde n 8.1 Tk "Tk Built-In Commands" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +dde \- Execute a Dynamic Data Exchange command +.SH SYNOPSIS +\fBdde ?\-async?\fR \fIcommand service topic \fR?\fIdata\fR? +.BE + +.SH DESCRIPTION +.PP +This command allows an application to send Dynamic Data Exchange (DDE) +command when running under Microsoft Windows. Dynamic Data Exchange is +a mechanism where applications can exchange raw data. Each DDE +transaction needs a \fIservice name\fR and a \fItopic\fR. Both the +\fIservice name\fR and \fItopic\fR are application defined; Tk uses +the service name \fBTk\fR, while the topic name is the name of the +interpreter given by \fBtk appname\fR. Other applications have their +own \fIservice names\fR and \fItopics\fR. For instance, Microsoft Excel +has the service name \fBExcel\fR. +.PP +The only option to the \fBsend\fR command is: +.TP +\fB\-async\fR +Requests asynchronous invocation. This is valid only for the +\fBexecute\fR subcommand. Normally, the \fBdde execute\fR subcommand +waits until the command completes, returning appropriate error +messages. When the \fB\-async\fR option is used, the command returns +immediately, and no error information is available. +.SH "DDE COMMANDS" +.PP +The following commands are a subset of the full Dynamic Data Exchange +set of commands. +.TP +\fBdde execute \fIservice topic data\fR +\fBdde execute\fR takes the \fIdata\fR and sends it to the server +indicated by \fIservice\fR with the topic indicated by +\fItopic\fR. Typically, \fIservice\fR is the name of an application, +and \fItopic\fR is a file to work on. The \fIdata\fR field is given +to the remote application. Typically, the application treats the +\fIdata\fR field as a script, and the script is run in the +application. The command returns an error if the script did not +run. If the \fB\-async\fR flag was used, the command +returns immediately with no error. +.TP +\fBdde request \fIservice topic item\fR +\fBdde request\fR is typically used to get the value of something; the +value of a cell in Microsoft Excel or the text of a selection in +Microsoft Word. \fIservice\fR is typically the name of an application, +\fItopic\fR is typically the name of the file, and \fIitem\fR is +application-specific. The command returns the value of \fIitem\fR as +defined in the application. +.TP +\fBdde services \fIservice topic\fR +\fBdde services\fR returns a list of service-topic pairs that +currently exist on the machine. If \fIservice\fR and \fItopic\fR are +both null strings ({}), then all service-topic pairs currently +available on the system are returned. If \fIservice\fR is null and +\fItopic\fR is not, then all services with the specified topic are +returned. If \fIservice\fR is not null and \fItopic\fR is, all topics +for a given service are returned. If both are not null, if that +service-topic pair currently exists, it is returned; otherwise, null +is returned. +.SH "DDE AND TK" +Tk always has a service name of "Tk". Each different interp of all +running Tk applications has a unique name. A list of running interps +can be retrieved using the \fBwinfo interps\fR command. A given +interp's name can be set with the \fBtk appname\fR. Each interp is +available as a DDE topic. So a \fBdde services Tk {}\fR command will +return a list of service-topic pairs, where each of the currently +running interps will be a topic. +.PP +When Tk processes a \fBdde execute\fR command, the data for the +execute is run as a script in the interp named by the topic of the +\fBdde execute\fR command. +.PP +When Tk processes a \fBdde request\fR command, it returns the value of +the variable given in the dde command in the context of the interp +named by the dde topic. Tk reserves the variable "$TK$EXECUTE$RESULT" +for internal use, and \fBdde request\fR commands for that variable +will give unpredictable results. +.PP +An external application which wishes to run a script in Tk should have +that script store its result in a variable, run the \fBdde execute\fR +command, and the run \fBdde request\fR to get the value of the +variable. +.SH KEYWORDS +application, dde, name, remote execution +.SH "SEE ALSO" +tk, winfo, send + |