BBS: Inland Empire Archive
Date: 04-14-92 (08:39) Number: 96
From: MATT HART Refer#: NONE
To: JASON GORMLEY Recvd: NO
Subj: Out of String Space Conf: (2) Quik_Bas
JG> OUT OF STRING SPACE. My question is this... Has anyone else had a
JG> problem with this, and what are my options in getting rid of this
JG> troblesome error??
Here's a canned message for explaining QB memory usage.
It'll help with understanding assembly linkage, string
space problems and solutions, and other advanced stuff.
Unless otherwise noted, all references will be to QB 4.5.
QB uses memory in several distinct ways. They are:
Code Segments
DGroup (Data Group)
Far Heap
First, Code Segments:
This is the actual EXE file space taken by your program's
instructions. It can be reduced by compiling with /O
(stand alone). The actual EXE file will be larger, but it
will probably have less than the BRUN45.EXE (also in the
code segment memory) and your EXE file put together. Also,
don't compile a final product with /D (debug). This bloats
your EXE file size by 5-10K and makes it slower. Use it
during programming only. Use /X (extended error trapping)
only when absolutely neccessary. When possible, move the
portion of code requiring /X to a SUB module, as it also
adds 5-10K of code. Any one .BAS source code file MUST
compile to less than 64K of code. More than one 64K file
can be linked together to create large EXE files, but this
stricture is required so that GOTO's and GOSUB's work
properly - they are near jumps within a segment of memory.
If a program makes lots of CALL's to the same routine, put
that CALL into a GOSUB. GOSUB's take only a few bytes, but
CALL's take 80 bytes plus a couple for every parameter.
Second, DGroup:
This is the most widely used and abused portion of QB. Out
of String Space, Out of Stack Space, String Space Corrupt, and
most "masked" error messages are a result of problems in dgroup
(a masked error is a recieved message (like String Space Corrupt)
that is not the ACTUAL error (which might have been a "Subscript
Out Of Range")). Dgroup is a fixed 64K segment of memory that
holds the following:
The Stack : Default size is 3K. This holds parameters used
in CALL's, return address' for CALL and GOSUB. Improperly
nested menus and GOSUB's without RETURN's will eventually
result in an Out Of Stack Space. Proper usage should allow
the 3K default to be plenty.
COMMON Data Area : Area used to track the address' of
variable in COMMON between CHAINed EXE programs and
between SUB/FUNCTION procedures and the main module.
Continued...
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* Origin: Midnight Micro! V.32/REL (918)451-3306 (1:170/600)
