Below is an example of a problem using the STRING$(32767,32) function
when compiled with the Generate 68020 Code or Generate 68881 Code
option.
The following code usually (incorrectly) gives error 57 ("Device I/O
Error") at run time on Apple System version 6.05. Sometimes Error 5
("Invalid Function Call") incorrectly occurs when the program tries to
print the FRE function after the string assignment a$ =
STRING$(32767,32). In other, different combinations of QuickBasic
versions, compiler options, and System versions, wrong screen output,
System Errors, or hanging may occur.
The program is compiled with all compiler options including "Use
default menus" and "Process events." The symptoms of this problem
depend upon the version of the Apple System software.
This problem occurs in Microsoft QuickBasic versions 1.00, 1.00a, and
1.00b for Macintosh Systems. Microsoft is researching this
problem and will post new information here in the Microsoft Knowledge Base
as it becomes available.
When you compile without the Generate 68020 Code or Generate 68881
Code options, or if you changed the string assignment to a$ =
STRING$(32766,32), no problem occurs.
If compiled using QuickBasic version 1.00b running on Apple System
version 6.05, you will get either error 57 or error 5.
When compiled with QuickBasic version 1.00b using System version 6.04
(other System versions not tested), the display of output is corrupt:
Instead of
data: 74096 stack: 12212 string: 78820
data: 74096 stack: 12212 string: xxxxx
you get the following:
data: 74096 stack: 12212 string: 78820
data: data:
74096 74096
stack: stack:
12212 12212
string: string: 78820
78820
When tested with System version 6.04 using QuickBasic version 1.00, a
system bomb ID=3 occurs when the program is compiled with either the
68020 or 68881 options.
Code Example
WINDOW 1,"",(10,25)-(500,500)
PRINT "data: ";FRE(-1);"stack: ";FRE(-2);"string: ";FRE("")
a$ = STRING$(32767,32)
PRINT "data: ";FRE(-1);"stack: ";FRE(-2);"string: ";FRE("")
INPUT x 'for a pause
WINDOW CLOSE 1
END