table of contents
Tcl_AppInit(3) | Tcl Library Procedures | Tcl_AppInit(3) |
NAME¶
Tcl_AppInit - perform application-specific initialization
SYNOPSIS¶
#include <tcl.h> int Tcl_AppInit(interp)
ARGUMENTS¶
- Tcl_Interp *interp (in)
- Interpreter for the application.
DESCRIPTION¶
Tcl_AppInit is a “hook” procedure that is invoked by the main programs for Tcl applications such as tclsh and wish. Its purpose is to allow new Tcl applications to be created without modifying the main programs provided as part of Tcl and Tk. To create a new application you write a new version of Tcl_AppInit to replace the default version provided by Tcl, then link your new Tcl_AppInit with the Tcl library.
Tcl_AppInit is invoked by Tcl_Main and Tk_Main after their own initialization and before entering the main loop to process commands. Here are some examples of things that Tcl_AppInit might do:
- [1]
- Call initialization procedures for various packages used by the application. Each initialization procedure adds new commands to interp for its package and performs other package-specific initialization.
- [2]
- Process command-line arguments, which can be accessed from the Tcl variables argv and argv0 in interp.
- [3]
- Invoke a startup script to initialize the application.
Tcl_AppInit returns TCL_OK or TCL_ERROR. If it returns TCL_ERROR then it must leave an error message in for the interpreter's result; otherwise the result is ignored.
In addition to Tcl_AppInit, your application should also contain a procedure main that calls Tcl_Main as follows:
Tcl_Main(argc, argv, Tcl_AppInit);
KEYWORDS¶
application, argument, command, initialization, interpreter
7.0 | Tcl |