Using an existing Console Window

[Ed Davis]

I do most of my work from a Windows command prompt/console box.

It would be nice for certain QB64 programs that I write, if all output went to the console window that I'm working in.

Using notes I found on the Wiki, I was able to get it to work:

Code: QB64: [Select]

1. $screenhide
2. $console
3. _console on
4. _dest _console
5.  
6. dim i%
7. do
8.     _limit 10
9.     i% = i% + 1
10.     print STR$(i%)
11. loop until i% > 15
12.  
13. system
14.  

If run while in a command prompt, all output goes to that command prompt.  Just what I wanted.

However, one problem remains: If I start the program from an icon, or via an explorer window, the window is closed after the program is finished (because of the system command).

How can I tell if my program was started from a console prompt or not, so I can selectively issue the system command?

[Ashish]

Simply pass a agruement to your program when running from CMD, like "yourProg.exe foo".
Then use COMMAND$ in your code to check whether it was run from console window.

Code: QB64: [Select]

1. $SCREENHIDE
2. $CONSOLE
3. _CONSOLE ON
4. _DEST _CONSOLE
5.  
6. DIM i%
7. DO
8.     _LIMIT 10
9.     i% = i% + 1
10.     PRINT STR$(i%)
11. LOOP UNTIL i% > 15
12.  
13. IF COMMAND$(1) = "foo" THEN SYSTEM
14.  

[Ed Davis]

Simply pass a agruement to your program when running from CMD, like "yourProg.exe foo".
Then use COMMAND$ in your code to check whether it was run from console window.

I appreciate the reply, but I don't want to have to pass a parameter.

In a Windows program written in C - one that uses the GUI subsystem, e.g., WinMain() instead of main(), one can call AttachConsole(ATTACH_PARENT_PROCESS), and if the function returns nonzero, the GUI program was started from a command prompt.

However, when I try this from QB64, it always returns 0, no matter how the program was started.