silk@dhw68k.cts.com (Mitch Gorman) (02/02/90)
In article <9620@nigel.udel.EDU> jacobs@freezer.it.udel.edu (michael jacobs) writes: >In article <476@n5pph007.UUCP> jlo@n5pph007.UUCP (Jackie O'Grady) writes: >=> program proga; /* proga calls progb */; >you're writing in Pascal, not C. Use { } :-) At least Jackie didn't make THAT mistake!! :^):^) >=> {$M 65500, 16384, 655360} >I'm assuming you have enough memory to run the program... THIS is where the troubles begin! If you only have 640k of memory, you CAN'T set the maximum heap size to the top of memory! You must save some. Best bet would be to compile proga, then do a Get info from the Compile menu. This'll tell you a rough size for your program. Add another, oh, 20k to be safe, and THAT is what you should set the last value of the $M compiler command to. >=> begin >=> clrscr; >=> writeln('in progb'); >=> exec('progb',''); >This is where the problem is. When you use EXEC, you are directly executing >the specified program, NOT going to an OS shell then executing a >command. So, you have to fully specify the path and full filename of >the program you want to run. If you DO want to shell to OS and use >it as a command line command, say >EXEC('c:\command.com','/c progb'); > or wherever command.com is... Yes, you do need to specify a full path. This eventually would've been another bug, but the memory allocation caught you first. You can do it as Michael has said, by passing your program name to a DOS shell; or, you can simply specify a complete path with progb as the first parameter to EXEC, with the second parameter an empty string (''). Either method will work, however the DOS shell will require more memory. No matter which way you do it, you should check the value of the predefined variable DosError (caps not required, defined in the DOS unit). This'll tell you if you've gotten an error in your child program. (Obviously it's gotta be one DOS can catch!) RTFM for possible values of DosError and their meanings. Mitch silk@dhw68k.cts.com