INT 0x21 - 0x00 - Program Terminate

This function is no longer recommended, but can be used by version of DOS before 2.0, see Int 0x21,0x4C and Int 0x21,0x00

reg value descr
AH 0x00
CS PSP segment adress


  • restores the terminate, Ctrl-Break, and critical error exit addresses, flushes all buffers, frees memory and returns to DOS via the termination handler address
  • does not close FCBs


  • back2root/ibm-pc-ms-dos/interrupts/int_21/int_21_00.txt
  • Dernière modification : 2023/01/16 17:54
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