freemem() in c

Frees a previously allocated DOS memory block
Declaration:
int freemem(unsigned segx);
Remarks:
freemem frees a memory block allocated by a previous call to allocmem.
segx is the segment address of the block.

Return Value:
On success, both functions return 0
On error,
_dos_freemem returns the DOS error code and sets errno to ENOMEM (Bad memory pointer)
freemem returns -1 and sets errno to ENOMEM (Insufficient memory)

program

#include <dos.h> #include <alloc.h> #include <stdio.h> int main(void) {    unsigned int size, segp;    int stat;    size = 64; /* (64 x 16) = 1024 bytes */    stat = allocmem(size, &segp);    if (stat < 0)       printf("Allocated memory at segment: %x\n", segp);    else       printf("Failed: maximum number of\              paragraphs available is %u\n", stat);    freemem(segp);    return 0; }

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