* = undocumented Function Description ---------- ------------------------------------------------------- Int\21f\00 terminate program Int\21f\01 get keyboard input Int\21f\02 display character to STDIO Int\21f\03 get character from STDAUX Int\21f\04 output character to STDAUX Int\21f\05 output character to STDPRN Int\21f\06 direct console I/O - keyboard to screen Int\21f\07 get char from std I/O without echo Int\21f\08 get char from std I/O without echo, checks for ^C Int\21f\09 display a string to STDOUT Int\21f\0A buffered keyboard input Int\21f\0B check STDIN status Int\21f\0C clear keyboard buffer and invoke keyboard function Int\21f\0D flush all disk buffers Int\21f\0E select disk Int\21f\0F open file with File Control Block Int\21f\10 close file opened with File Control Block Int\21f\11 search for first matching file entry Int\21f\12 search for next matching file entry Int\21f\13 delete file specified by File Control Block Int\21f\14 sequential read from file specified by File Control Block Int\21f\15 sequential write to file specified by File Control Block Int\21f\16 find or create firectory entry for file Int\21f\17 rename file specified by file control block Int\21f\18* unknown Int\21f\19 return current disk drive Int\21f\1A set disk transfer area (DTA) Int\21f\1B get current disk drive FAT Int\21f\1C get disk FAT for any drive Int\21f\1D* unknown Int\21f\1E* unknown Int\21f\1F* read DOS disk block, default drive Int\21f\20* unknown Int\21f\21 random read from file specified by Struct -FCB Int\21f\22 random write to file specified by Struct -FCB Int\21f\23 return number of records in file specified by Struct -FCB Int\21f\24 set relative file record size field for file Struct -FCB Int\21f\25 set interrupt vector Int\21f\26 create new Program Segment Prefix (PSP) Int\21f\27 random file block read from file specified by Struct -FCB Int\21f\28 random file block write to file specified by Struct -FCB Int\21f\29 parse the command line for file name Int\21f\2A get the system date Int\21f\2B set the system date Int\21f\2C get the system time Int\21f\2D set the system time Int\21f\2E set/clear disk write VERIFY Int\21f\2F get the Disk Transfer Address (DTA) Int\21f\30 get DOS version number Int\21f\31 TSR, files opened remain open Int\21f\32* read DOS Disk Block Int\21f\33 get or set Ctrl-Break Int\21f\34* INDOS Critical Section Flag Int\21f\35 get segment and offset address for an interrupt Int\21f\36 get free disk space Int\21f\37* get/set option marking character (SWITCHAR) Int\21f\38 return country-dependent information Int\21f\39 create subdirectory Int\21f\3A remove subdirectory Int\21f\3B change current directory Int\21f\3C create and return file handle Int\21f\3D open file and return file handle Int\21f\3E close file referenced by file handle Int\21f\3F read from file referenced by file handle Int\21f\40 write to file referenced by file handle Int\21f\41 delete file Int\21f\42 move file pointer (move read-write pointer for file) Int\21f\43 set/return file attributes Int\21f\44 device IOCTL (I/O control) info Int\21f\45 duplicate file handle Int\21f\46 force a duplicate file handle Int\21f\47 get current directory Int\21f\48 allocate memory Int\21f\49 release allocated memory Int\21f\4A modify allocated memory Int\21f\4B load or execute a program Int\21f\4C terminate prog and return to DOS Int\21f\4D get return code of subprocess created by 4Bh Int\21f\4E find first matching file Int\21f\4F find next matching file Int\21f\50* set new current Program Segment Prefix (PSP) Int\21f\51* puts current PSP into BX Int\21f\52* pointer to the DOS list of lists Int\21f\53* translates BPB (Bios Parameter Block, see below) Int\21f\54 get disk verification status (VERIFY) Int\21f\55* create PSP: similar to function 26h Int\21f\56 rename a file Int\21f\57 get/set file date and time Int\21f\58 get/set allocation strategy (DOS 3.x) Int\21f\59 get extended error information Int\21f\5A create a unique filename Int\21f\5B create a DOS file Int\21f\5C lock/unlock file contents Int\21f\5D* network Int\21f\5E* network Int\21f\5F* network redirection Int\21f\60* parse pathname Int\21f\61* unknown Int\21f\62 get program segment prefix (PSP) Int\21f\63* get lead byte table (DOS 2.25) Int\21f\64* unknown Int\21f\65 get extended country information (DOS 3.3) Int\21f\66 get/set global code page table (DOS 3.3) Int\21f\67 set handle count (DOS 3.3) Int\21f\68 commit file (DOS 3.3) Int\21f\69 disk serial number (DOS 4.0) Int\21f\6A unknown Int\21f\6C extended open/create (DOS 4.0)