DosSubFreeMem frees a block of memory that was previously allocated by DosSubAllocMem.

cb should be a multiple of 8 bytes, otherwise it will be rounded up. The maximum value for the cb parameter is the size of the memory pool initialized by DosSubSetMem minus 64 bytes.

Note: DosAllocMem and DosAllocSharedMem both allocate a block of memory of the size requested rounded to the nearest page. On OS/2 Warp, the system allocates a 64K object without attributes on every allocation.

For example, for a DosAllocMem call with a size of 1, the following occurs:

• On OS/2 Warp Connect, the system allocates a 4096-byte block of committed memory.
  
• On OS/2 Warp, the system allocates a 4096-byte block of committed memory plus 61440 bytes without attributes.

Note:

When you allocate a memory object with the PAG_EXECUTE attribute, it is implied that this memory object also has the PAG_READ attribute. However, when querying the attributes of a memory object, you will get the following results:

• On OS/2 Warp Connect, both PAG_EXECUTE and PAG_READ attributes are returned.

• On OS/2 Warp, only the PAG_EXECUTE attribute is returned. However, PAG_READ is still implied.