ID Number: Q63052
1.00
MS-DOS
buglist1.00 fixlist1.10
Summary:
Extensions written for use by the Programmer's WorkBench (PWB) version
1.0 under the DOS operating system are recognized as returning true
regardless of their actual return values.
Microsoft has confirmed this to be a problem in PWB version 1.0. This
problem was corrected in PWB version 1.1.
More Information:
The use of return values as a way of providing conditional jumps
inside PWB macros is a common practice that is affected by the above
limitation for PWB extensions. The sample extension and macros below
demonstrate the above problem. Once installed, both the f1() and f2()
functions will be seen as returning true to PWB.
Sample Code
-----------
// TEST.C
#include <string.h>
#include <stdlib.h>
#include <ext.h>
PWBFUNC f1( unsigned argData, ARG far *pArg, flagType fMeta );
PWBFUNC f2( unsigned argData, ARG far *pArg, flagType fMeta);
// Switches.
struct swiDesc swiTable[] =
{
{ NULL, NULL, 0 }
};
// Commands.
struct cmdDesc cmdTable[] =
{
{ "f1", f1, 0, NOARG },
{ "f2",f2,0, NOARG },
{ NULL, NULL, 0, 0 }
};
void EXTERNAL WhenLoaded()
{
SetKey( "f1", "alt+f" );
SetKey( "f2", "ctrl+f" );
return;
}
PWBFUNC f1( unsigned argData, ARG far *pArg, flagType fMeta )
{
return(FALSE); /* FALSE is defined as 0 in ext.h */
}
PWBFUNC f2( unsigned argData, ARG far *pArg, flagType fMeta)
{
return(TRUE); /* TRUE is defined as 1 in ext.h */
}
// End of TEST.C
Sample Macros
-------------
; sample macros for TOOLS.INI to test f1 and f2
load f1
test:=f1 ->loc1 arg "true" message => :>loc1 arg "false" message
test2:=f2 ->loc2 arg "true" message => :>loc2 arg "false" message
test:alt+t
test2:ctrl+2
Additional reference words: 1.00