diff -r 08ec8eefde2f -r c084286672be persistentstorage/sqlite3api/TEST/TCL/tcldistribution/mac/Background.doc --- a/persistentstorage/sqlite3api/TEST/TCL/tcldistribution/mac/Background.doc Fri Jan 22 11:06:30 2010 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,92 +0,0 @@ -Notes about the Background Only application template -==================================================== - -RCS: @(#) $Id: Background.doc,v 1.2 1998/09/14 18:40:03 stanton Exp $ - -We have included sample code and project files for making a Background-Only - application (BOA) in Tcl. This could be used for server processes (like the -Tcl Web-Server). - -Files: ------- - -* BOA_TclShells.¼ - This is the project file. -* tclMacBOAAppInit.c - This is the AppInit file for the BOA App. -* tclMacBOAMain - This is a replacement for the Tcl_Main for BOA's. - -Caveat: -------- - -This is an unsupported addition to MacTcl. The main feature that will certainly -change is how we handle AppleEvents. Currently, all the AppleEvent handling is -done on the Tk side, which is not really right. Also, there is no way to -register your own AppleEvent handlers, which is obviously something that would be -useful in a BOA App. We will address these issues in Tcl8.1. If you need to -register your own AppleEvent Handlers in the meantime, be aware that your code -will probably break in Tcl8.1. - -I will also improve the basic code here based on feedback that I recieve. This -is to be considered a first cut only at writing a BOA in Tcl. - -Introduction: -------------- - -This project makes a double-clickable BOA application. It obviously needs -some Tcl code to get it started. It will look for this code first in a -'TEXT' resource in the application shell whose name is "bgScript.tcl". If -it does not find any such resource, it will look for a file called -bgScript.tcl in the application's folder. Otherwise it will quit with an -error. - -It creates three files in the application folder to store stdin, stdout & -stderr. They are imaginatively called temp.in, temp.out & temp.err. They -will be opened append, so you do not need to erase them after each use of -the BOA. - -The app does understand the "quit", and the "doScript" AppleEvents, so you can -kill it with the former, and instruct it with the latter. It also has an -aete, so you can target it with Apple's "Script Editor". - -For more information on Macintosh BOA's, see the Apple TechNote: 1070. - -Notifications: --------------- - -BOA's are not supposed to have direct contact with the outside world. They -are, however, allowed to go through the Notification Manager to post -alerts. To this end, I have added a Tcl command called "bgnotify" to the -shell, that simply posts a notification through the notification manager. - -To use it, say: - -bgnotify "Hi, there little buddy" - -It will make the system beep, and pop up an annoying message box with the -text of the first argument to the command. While the message is up, Tcl -is yielding processor time, but not processing any events. - -Errors: -------- - -Usually a Tcl background application will have some startup code, opening -up a server socket, or whatever, and at the end of this, will use the -vwait command to kick off the event loop. If an error occurs in the -startup code, it will kill the application, and a notification of the error -will be posted through the Notification Manager. - -If an error occurs in the event handling code after the -vwait, the error message will be written to the file temp.err. However, -if you would like to have these errors post a notification as well, just -define a proc called bgerror that takes one argument, the error message, -and passes that off to "bgnotify", thusly: - -proc bgerror {mssg} { - bgnotify "A background error has occured\n $mssg" -} - -Support: --------- - -If you have any questions, contact me at: - -jim.ingham@eng.sun.com