Int 31 Fn FF24  P - Causeway - "execoverlay" - Load And Optionally Execut  [E]

   AX = FF24h
   EBX = flags
       bit 0: don't execute (overlay only)
       bit 1: don't preserve relocation information
   ES:EDX -> filename (see also #2834)
   FS:ESI -> commandline (ESI = 00000000h if no commandline)
   GS:EDI -> name (CW's /o option)

Return: CF clear if successful
       ---EBX bit 0 set---
       CX:EDX = program entry point (CS:EIP)
       SI = segment of PSP
       ---EBX bit 1 set---
       BX:EAX = initial SS:ESP
       EDI high word = base segment
       EDI low word = number of segments
       EBP = start of segment definitions
   CF set on error
       AX = error code
       0001h DOS file access error
       0002h not a CuaseWay 3P file
       0003h not enough memory

See Also: AX=FF2Ah,INT 21/AH=4Bh

Format of CauseWay executable:
Offset Size    Description (Table 2834)
 00h  2 BYTEs  signature "3P"
 02h   DWORD   size of header data in bytes
 06h   DWORD   size of EXE image data in bytes
 0Ah   DWORD   number of bytes of program memory required
 0Eh   WORD    number of segment definitions (see #2836)
 10h   DWORD   number of relocation table entries
 14h   DWORD   offset of program entry point
 18h   WORD    segment list entry number for entry point's CS
 1Ah   DWORD   initial ESP
 1Eh   WORD    segment list entry number for initial SS
 20h   DWORD   control flags (see #2835)
 24h   DWORD   automatic stack size in bytes if ESP entry = 00000000h
 28h   BYTE    length of name (name follows program image)
 29h 23 BYTEs  reserved

See Also: #1280,#1295 at INT 21/AH=4Bh

Bitfields for CauseWay executable control flags:
Bit(s) Description (Table 2835)
 0 16-bit interrupt stack frame
 7 descriptor table type (0 = GDT, 1 = LDT)
 14    16-bit default data size
 31    compressed EXE image

Note:  bits 0 and 14 should always be equal

See Also: #2834

Format of CauseWay segment definition [array]:
Offset Size    Description (Table 2836)
 00h   DWORD   start offset within program image
 04h   DWORD   length and type
       bits 0-19: length
       bit 20:    granularity (if set, length is in 4K pages)
       bits 21-24: type
           0000 code
           0001 read/write data
           0010 stack
           0011 read-only data
       bit 25: force segment descriptor's D bit to 0
       bit 26: force segmetn descriptor's D bit to 1

See Also: #2834