BBC BASIC Programmers' Reference

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
=====Discovering how a program was run=====

//by Jon Ripley, May 2006//\\ \\  In some cases it is important to know what environment your program is running in so you can make different choices to suit the environment.\\ \\  There are three methods to run a BBC BASIC program:\\ 

  * From the BBC BASIC Editor (IDE)
  * An uncompiled program run using the interpreter
  * Running a compiled program
\\  To determine the environment a program is running in use code similar to the following:\\ 
<code bb4w>
        SYS "GetCommandLine" TO cmd%
        CASE TRUE OF
          WHEN INSTR($$cmd%, "bbcwin.exe") > 0:PRINT "Run from editor"
          WHEN INSTR($$cmd%, "bbcwrun.exe") > 0:PRINT "Run by interpreter"
          OTHERWISE:PRINT "Program is compiled"
        ENDCASE
</code>
Here we read a pointer to the command line arguments used to start the program and **PRINT** a different response for each possible case. It is not possible to use the special variable **@cmd$** as this contains insufficient information.\\ \\  Refactoring this code into a function is simple:\\ 
<code bb4w>
        DEF FN_GetRunEnvironment
        LOCAL cmd%, ret%
        SYS "GetCommandLine" TO cmd%
        CASE TRUE OF
          WHEN INSTR($$cmd%, "bbcwin.exe") > 0:ret%=1
          WHEN INSTR($$cmd%, "bbcwrun.exe") > 0:ret%=2
          OTHERWISE:ret%=3
        ENDCASE
        =ret%
</code>
Here we create a function named **FN_GetRunEnvironment** which returns one of three possible values:\\ \\ 

  * **1** - Program was run from the editor
  * **2** - Program was run using the interpreter
  * **3** - Program is compiled
\\
----
\\ //by Richard Russell, November 2010//\\ \\  If you want to know whether a program is compiled or not, you can use this simple test:\\ 
<code bb4w>
        IF INSTR(@lib$,@tmp$) THEN PRINT "Program is compiled"
</code>