HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

              INT 21,3F - Read From File or Device Using Handle


       AH = 3F
       BX = file handle
       CX = number of bytes to read
       DS:DX = pointer to read buffer


       on return:
       AX = number of bytes read is CF not set
          = error code if CF set  (see DOS ERROR CODES)


       - read specified number of bytes from file into buffer DS:DX
       - when AX is not equal to CX then a partial read occurred due
         to end of file
       - if AX is zero, no data was read, and EOF occurred before read

Esc or Alt-X to exit int 21,3f Home/PgUp/PgDn/End ←↑↓→