National Instruments 320685D-01 ユーザーズマニュアル

Chapter 4

Windows 3.1 Compiler/Linker Issues

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 National Instruments Corporation

4-17

LabWindows/CVI Programmer Reference Manual

Then assume that a program in LabWindows/CVI uses the function 

f

 as follows:

char *bufptr;

bufptr = f();

printf("%s", bufptr);

You would have to modify the glue code as shown here:

char * f(char *ptr)

{

char *retval;

unsigned short  cw387;

char *ptr, *tmpPtr, _far *farPtr32, _far *tmpFarPtr32;

int i;

cw387 = Get387CW();

retval = (char *) InvokeIndirectFunction(__static_f, ptr);

Set387CW(cw387);

/* convert the 16 bit far pointer to a 32 bit far pointer*/

farPtr32 = MK_FP32(retval);

tmpFarPtr32 = farPtr32;

/* Calculate the length of the string. Cannot call strlen*/

/* because it does not accept far pointers. 

*/

i = 0

while (*tmpFarPtr32++)

i++;

/* Allocate buffer from CVI memory and copy in data. 

*/

if ((ptr = malloc(i + 1)) != NULL) {

tmpFarPtr32 = farPtr32;

tmpPtr = ptr;

while (*tmpPtr++ = *tmpFarPtr32++);

}

return ptr;

}

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