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diff --git a/xpa/doc/tcl.html b/xpa/doc/tcl.html deleted file mode 100644 index 8feb46a..0000000 --- a/xpa/doc/tcl.html +++ /dev/null @@ -1,249 +0,0 @@ -<!-- =defdoc xpatcl xpatcl n --> -<HTML> -<HEAD> -<TITLE>XPA/Tcl Interface</TITLE> -</HEAD> -<BODY> - -<!-- =section xpatcl NAME --> -<H2><A NAME="xpatcl">XPATcl: the XPA Interface to the Tcl/Tk Environment</A></H2> - -<!-- =section xpatcl SYNOPSIS --> -<H2>Summary</H2> - -<P> -Tcl/Tk programs can act as XPA clients and/or servers using the Tcl -interface to XPA that is contained in the libtclxpa.so shared object. - -<H2>Server Routines</H2> - -<PRE> - set xpa [xpanew class name help sproc sdata smode rproc rdata rmode] - xpafree xpa - set xpa [xpanew class name help iproc idata imode] - set xpa [xpacmdnew class name] - xpacmdadd xpa name help sproc sdata smode rproc rdata rmode - xpacmddel xpa cmd - set val [xparec xpa option] - options: name, class, method, cmdfd, datafd, cmdchan, datachan - xpasetbuf xpa buf len - xpaerror xpa message - xpamessage xpa message -</PRE> - -<H2>Client Routines</H2> - -<PRE> - set xpa [xpaopen mode] - xpaclose xpa - set got [xpaget xpa template paramlist mode bufs lens names errs n] - set got [xpaget xpa template paramlist mode chans names errs n] - set got [xpaset xpa template paramlist mode buf len names errs n] - set got [xpasetfd xpa template paramlist mode chan names errs n] - set got [xpainfo xpa template paramlist mode names errs n] - # NB: 2.1 calling sequence change - # set got [xpaaccess template type] (2.0.5) - set got [xpaaccess xpa template paramlist mode names errs n] - set got [xpanslookup template type classes names methods] -</PRE> - -<!-- =section xpatcl DESCRIPTION --> -<H2>Description</H2> -<P> -You can call XPANew(), XPACmdNew(), or XPAInfoNew() within a C -routine to add C-based XPA server callbacks to a TCL/Tk program that -uses a Tcl/Tk event loop (either vwait() or the Tk event loop); -Such a program does not need or want to use the XPA event loop. -Therefore, in order to add XPA access points to the Tcl/Tk loop, the -following routine should be called beforehand: -<PRE> - int XPATclAddInput(XPA xpa); -</PRE> -<P> -Normally, the xpa argument is NULL, meaning that all current XPA -access points are registered with the event loop. However, if a -single XPA access point is to be added (i.e., after the event loop is -started) then the handle of that XPA access point can be passed to -this routine. - -<P> -The significance of the XPA/TCL interface goes beyond the support for -using XPA inside C code. The interface allows you to write XPA -servers and to make calls to the XPA client interface within the Tcl -environment using the Tcl language directly. The XPA/Tcl -interface can be loaded using the following package command: -<PRE> - package require tclxpa 2.0 -</PRE> -Alternatively, you can load the shared object (called libtclxpa.so ) directly: -<PRE> - load .../libtclxpa.so tclxpa -</PRE> -<P> -Once the tclxpa package is loaded, you can use Tcl versions of XPA -routines to define XPA servers or make client XPA calls. The -interface for these routines is designed to match the Unix XPA -interface as nearly as possible. Please refer to -<A HREF="./server.html">XPA Servers</A> -and -<A HREF="./client.html">XPA Clients</A> -for general information about these routines. - -<P> -The file test.tcl in the XPA source directory gives examples for using the -XPA/Tcl interface. - -<P> -The following notes describe the minor differences between the interfaces. - -<H2><A NAME="xpanew">XPANew</A></H2> -<PRE> -<B> - set xpa [xpanew class name help sproc sdata smode rproc rdata rmode] -</B> -</PRE> -<P> -rproc and sproc routines are routines. The calling sequence of the -rproc routine is identical to its C counterpart: -<PRE> - proc rec_cb { xpa client_data paramlist buf len } { ... } -</PRE> -<P> -The sproc routine, however is slightly different from its C counterpart -because of the difficulty of passing data back from the callback to C: -<PRE> - proc sendcb { xpa client_data paramlist } { ... } -</PRE> -<P> -Note that the C-based server's char **buf and int *len arguments are -missing from the Tcl callback. This is because we did not know how to -fill buf with data and pass it back to the C routines for communication -with the client. Instead, the Tcl server callback uses the following -routine to set buf and len: -<PRE> - xpasetbuf xpa buf len -</PRE> -where: -<PRE> - arg explanation - ------ ----------- - xpa the first argument of the server callback - buf the data to be returned to the client - len data length in bytes, (if absent, use length of the buf object) -</PRE> -<P> -When this routine is called, a copy of buf is saved for transmission to -the client. - -<P> -The fact that buf is duplicated means that TCL server writers might wish to -perform the I/O directly within the callback, rather than have XPA do it -automatically at the end of the routine. To do this, set: -<PRE> - fillbuf=false -</PRE> -<P> -in the xpanew smode and then perform I/O through the Tcl channel -obtained from: -<PRE> - set dchan [xparec $xpa datachan] -</PRE> -<P> -where: -<PRE> - arg explanation - ------ ----------- - xpa the first argument of the server callback - datachan literal string "datachan" that returns the data channel - len data length in bytes, (if absent, use length of the buf object) -</PRE> -<P> -<B> -NB: datachan and cmdchan are not available under Windows. It is -necessary to use the "raw" equivalents: datafd and cmdfd. -</B> - -<P> -The same considerations apply to the rproc for receive servers: a copy -of the incoming data is generated to pass to the receive callback. This -copy again can be avoided by using "fillbuf=false" in the rmode and then -reading the incoming data from datachan. - -<P> -The send and receive callback routines can use the xpaerror and xpamessage -routines to send errors and messages back to the client. If you also -want tcl itself to field an error condition, use the standard return call: -<PRE> - return ?-code c? ?-errorinfo i? ?-errorcode ec? string -</PRE> -<P> -See the Tcl man page for more info. - -<H2><A NAME="xpanew">XPARec</A></H2> -<P> -The Tcl xparec procedure supplies server routines with access to information -that is available via macros in the C interface: -<PRE> - set val [xparec xpa <option>] -</PRE> -<P> -where option is: name, class, method, cmdfd, datafd, cmdchan, -datachan. Note that two additional identifiers, cmdchan and datachan, -have been added to to provide Tcl channels corresponding to datafd and -cmdfd. (These latter might still be retrieved in Tcl and passed back -to a C routines.) An additional option called "version" can be used to -determine the XPA version used to build the Tcl interface. Note that -the standard options require a valid XPA handle, but "version" does -not (since it simply reports the value of the XPA_VERSION definition -in the XPA source include file). - -<P> -<B> -NB: datachan and cmdchan are not available under Windows. It is -necessary to use the "raw" equivalents: datafd and cmdfd. -</B> -<PRE> - macro explanation - ------ ----------- - class class of this xpa - name name of this xpa - method method string (inet or local connect info) - cmdchan Tcl channel of command socket - datachan Tcl channel of data socket - cmdfd fd of command socket - datafd fd of data socket - sendian endian-ness of server ("little" or "big") - cendian endian-ness of client ("little" or "big" - version XPA version used to build this code -</PRE> - -<p> -Under Windows, the Tcl event handler cannot automatically sense when an -XPA socket is ready for IO (i.e. Tcl_CreateFileHandler() is not available -under Windows). The Windows Tcl event handler therefore must be awakened -occasionally for check for XPA events. This is done using the standard -Tcl_SetMaxBlockTime() call. The time parameter is defined in tclloop.c -and is currently set to 1000 microseconds (1/1000 of a second). - -<P> -The version option can be used to differentiate between source code versions. -It was created to support legacy Tcl code that needs to maintain the 2.0.5 -calling sequence for xpaaccess. You can use a version test such as: -<PRE> - if [catch { xparec "" version } version] { - puts "pre-2.1.0e" - } else { - puts [split $version .] - } -<PRE> - -<!-- =section xpatcl SEE ALSO --> -<!-- =text See xpa(n) for a list of XPA help pages --> -<!-- =stop --> - -<P> -<A HREF="./help.html">Go to XPA Help Index</A> - -<H5>Last updated: September 10, 2003</H5> -</BODY> -</HTML> |