Outils pour utilisateurs
back2root:ibm-pc-ms-dos:interrupts:int_21:int_21_4a
Table des matières
INT 0x21 - 0x4a - DOS 2+ - Resize Memory Block
This function :
- modifies memory block allocated by int 0x21 - 0x48.
- can be used by program to shrink or increase the size of allocated memory
Request/Call:
| reg | value | descr |
|---|---|---|
| AH | 0x4a | |
| BX | New memory size in paragraph | |
| ES | segment (block) to resize |
Return:
CF is cleared if successful
CF is Set if error
| reg | descr |
|---|---|
| AX | Error Code (0x07, 0x08, 0x09) (See Int 0x21, 0x59, Dos Error Code) |
| BX | maximum paragraphs available for specified memory block |
Notes & Comments
- PC-DOS 2.1 and DOS 3.x will allocate the largest available block if CF is set. BX will equal the size allocated.
- under DOS 2.1-5.0, if there is insufficient memory to expand the block as much as requested, the block will be made as large as possible
- DOS 2.1-5.0 coalesces any free blocks immediately following the block to be resized
back2root/ibm-pc-ms-dos/interrupts/int_21/int_21_4a.txt · Dernière modification : 2023/01/16 17:54 de frater
Outils de la page
Sauf mention contraire, le contenu de ce wiki est placé sous les termes de la licence suivante : CC Attribution-Noncommercial-Share Alike 4.0 International
