MS-DOS v2.0 Release

1 files changed, 963 insertions, 0 deletions

diff --git a/v2.0/source/DOSSYM_v211.ASM b/v2.0/source/DOSSYM_v211.ASM
new file mode 100644
index 0000000..106e115
--- /dev/null
+++ b/v2.0/source/DOSSYM_v211.ASM
@@ -0,0 +1,963 @@
+include DOSMAC.ASM
+IF2
+    %OUT    DOSSYM in Pass 2
+ENDIF
+
+IFNDEF  ALTVECT
+ALTVECT EQU     0       ;FALSE
+ENDIF
+
+DOS_MAJOR_VERSION   EQU      2
+DOS_MINOR_VERSION   EQU     11
+
+BREAK <Control character definitions>
+
+c_DEL       EQU     7Fh         ;    ASCII rubout or delete previous char
+c_BS        EQU     08h         ; ^H ASCII backspace
+c_CR        EQU     0Dh         ; ^M ASCII carriage return
+c_LF        EQU     0Ah         ; ^J ASCII linefeed
+c_ETB       EQU     17h         ; ^W ASCII end of transmission
+c_NAK       EQU     15h         ; ^U ASCII negative acknowledge
+c_ETX       EQU     03h         ; ^C ASCII end of text
+c_HT        EQU     09h         ; ^I ASCII tab
+
+BREAK <BPB Definition>
+
+
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+; Certain structures, constants and system  calls  below  are  private  to ;
+; the DOS  and  are  extremely  version-dependent.  They may change at any ;
+; time at  the  implementors'  whim.   As  a  result,  they  must  not  be ;
+; documented to  the  general  public.   If  an  extreme case arises, they ;
+; must be documented with this warning.                                    ;
+;                                                                          ;
+; Those structures and constants that are subject to  the  above  will  be ;
+; marked and bracketed with the flag:                                      ;
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK  <Bios Parameter Block>
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+
+; Bios Parameter Block definition
+; This structure is used to build a full DPB
+
+BPBLOCK STRUC
+BPSECSZ DW      ?       ; Size in bytes of physical sector
+BPCLUS  DB      ?       ; Sectors/Alloc unit
+BPRES   DW      ?       ; Number of reserved sectors
+BPFTCNT DB      ?       ; Number of FATs
+BPDRCNT DW      ?       ; Number of directory entries
+BPSCCNT DW      ?       ; Total number of sectors
+BPMEDIA DB      ?       ; Media descriptor byte
+BPFTSEC DW      ?       ; Number of sectors taken up by one FAT
+BPBLOCK ENDS
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK <Disk I/O Buffer Header>
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+
+; Field definition for I/O buffer information
+
+BUFFINFO        STRUC
+NEXTBUF         DD      ?       ; Pointer to next buffer in list
+; The next two items are often refed as a word
+BUFDRV          DB      ?       ; Logical drive # assoc with buffer FF = free
+BUFDIRTY        DB      ?       ; Dirty flag
+BUFPRI          DB      ?       ; Buffer selection priority (see EQUs below)
+VISIT           DB      ?       ; Visit flag for buffer pool scans
+BUFSECNO        DW      ?       ; Sector number of buffer
+; The next two items are often refed as a word
+BUFWRTCNT       DB      ?       ; For FAT sectors, # times sector written out
+BUFWRTINC       DB      ?       ; "   "     "   , # sectors between each write
+BUFDRVDP        DD      ?       ; Pointer to drive parameters
+BUFFINFO        ENDS
+
+BUFINSIZ        EQU     SIZE BUFFINFO
+                                ; Size of structure in bytes
+
+FREEPRI EQU     0
+LBRPRI  EQU     2               ; Last byte of buffer read
+LBWPRI  EQU     4               ; Last byte written
+RPRI    EQU     6               ; Read but not last byte
+WPRI    EQU     8               ; Written but not last byte
+DIRPRI  EQU     15              ; Directory Sector
+FATPRI  EQU     30              ; FAT sector
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK <User stack inside of system call>
+; Location of user registers relative user stack pointer
+
+user_environ    STRUC
+user_AX     DW      ?
+user_BX     DW      ?
+user_CX     DW      ?
+user_DX     DW      ?
+user_SI     DW      ?
+user_DI     DW      ?
+user_BP     DW      ?
+user_DS     DW      ?
+user_ES     DW      ?
+user_IP     DW      ?
+user_CS     DW      ?
+user_F      DW      ?
+user_environ    ENDS
+
+BREAK <interrupt definitions>
+
+INTTAB          EQU     20H
+INTBASE         EQU     4 * inttab
+ENTRYPOINT      EQU     INTBASE+40H
+
+        IF      ALTVECT
+ALTTAB  EQU     0F0H
+ALTBASE EQU     4 * ALTTAB
+        ENDIF
+
+;
+; interrupt assignments
+;
+        IF      NOT ALTVECT
+int_abort           EQU     INTTAB          ; abort process
+int_command         EQU     int_abort+1     ; call MSDOS
+int_terminate       EQU     int_abort+2     ; int to terminate address
+int_ctrl_c          EQU     int_abort+3     ; ^c trapper
+int_fatal_abort     EQU     int_abort+4     ; hard disk error
+int_disk_read       EQU     int_abort+5     ; logical sector disk read
+int_disk_write      EQU     int_abort+6     ; logical sector disk write
+int_keep_process    EQU     int_abort+7     ; terminate program and stay
+                                            ; resident
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+int_spooler         EQU     int_abort+8     ; spooler call
+int_fastcon         EQU     int_abort+9     ; fast CON interrupt
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+        ELSE
+int_abort           EQU     INTTAB          ; abort process
+int_command         EQU     int_abort+1     ; call MSDOS
+int_terminate       EQU     ALTTAB          ; int to terminate address
+int_ctrl_c          EQU     int_terminate+1 ; ^c trapper
+int_fatal_abort     EQU     int_terminate+2 ; hard disk error
+int_disk_read       EQU     int_abort+5     ; logical sector disk read
+int_disk_write      EQU     int_abort+6     ; logical sector disk write
+int_keep_process    EQU     int_abort+7     ; terminate program and stay
+                                            ; resident
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+int_spooler         EQU     int_terminate+3 ; spooler call
+int_fastcon         EQU     int_abort+9     ; fast CON interrupt
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+        ENDIF
+
+addr_int_abort          EQU    4 * int_abort
+addr_int_command        EQU    4 * int_command
+addr_int_terminate      EQU    4 * int_terminate
+addr_int_ctrl_c         EQU    4 * int_ctrl_c
+addr_int_fatal_abort    EQU    4 * int_fatal_abort
+addr_int_disk_read      EQU    4 * int_disk_read
+addr_int_disk_write     EQU    4 * int_disk_write
+addr_int_keep_process   EQU    4 * int_keep_process
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+addr_int_spooler        EQU    4 * int_spooler
+addr_int_fastcon        EQU    4 * int_fastcon
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK <Disk map>
+;  MSDOS partitions the disk into 4 sections:
+;
+;  phys sector 0:   +-------------------+
+;       |           | boot/reserved     |
+;       |           +-------------------+
+;       |           |  File allocation  |
+;       v           |      table(s)     |
+;                   |  (multiple copies |
+;                   |     are kept)     |
+;                   +-------------------+
+;                   |     Directory     |
+;                   +-------------------+
+;                   |     File space    |
+;                   +-------------------+
+;                   |   Unaddressable   |
+;                   |  (to end of disk) |
+;                   +-------------------+
+;
+; All partition boundaries are sector boundaries.  The size of the FAT is
+; adjusted to maximize the file space addressable.
+
+BREAK <Directory entry>
+
+;
+;       +---------------------------+
+;       |  (12 BYTE) filename/ext   |       0       0
+;       +---------------------------+
+;       |     (BYTE) attributes     |       11      B
+;       +---------------------------+
+;       |    (10 BYTE) reserved     |       12      C
+;       +---------------------------+
+;       | (WORD) time of last write |       22      16
+;       +---------------------------+
+;       | (WORD) date of last write |       24      18
+;       +---------------------------+
+;       |   (WORD) First cluster    |       26      1A
+;       +---------------------------+
+;       |     (DWORD) file size     |       28      1C
+;       +---------------------------+
+;
+;   First byte of filename  = E5 -> free directory entry
+;                           = 00 -> end of allocated directory
+;   Time:   Bits 0-4=seconds/2, bits 5-10=minute, 11-15=hour
+;   Date:   Bits 0-4=day, bits 5-8=month, bits 9-15=year-1980
+;
+dir_entry   STRUC
+dir_name    DB      11 DUP (?)          ; file name
+dir_attr    DB      ?                   ; attribute bits
+dir_pad     DB      10 DUP (?)          ; reserved for expansion
+dir_time    DW      ?                   ; time of last write
+dir_date    DW      ?                   ; date of last write
+dir_first   DW      ?                   ; first allocation unit of file
+dir_size_l  DW      ?                   ; low 16 bits of file size
+dir_size_h  DW      ?                   ; high 16 bits of file size
+dir_entry   ENDS
+
+attr_read_only      EQU      1h
+attr_hidden         EQU      2h
+attr_system         EQU      4h
+attr_volume_id      EQU      8h
+attr_directory      EQU     10h
+attr_archive        EQU     20h
+
+attr_all            EQU     attr_hidden+attr_system+attr_directory
+                                        ; OR of hard attributes for FINDENTRY
+
+attr_ignore         EQU     attr_read_only+attr_archive
+                                        ; ignore this(ese) attribute(s) during
+                                        ; search first/next
+
+attr_changeable     EQU     attr_read_only+attr_hidden+attr_system+attr_archive
+                                        ; changeable via CHMOD
+
+BREAK <File allocation Table information>
+;
+; The File Allocation Table uses a 12-bit entry for each allocation unit on
+; the disk.  These entries are packed, two for every three bytes.  The contents
+; of entry number N is found by 1) multiplying N by 1.5; 2) adding the result
+; to the base address of the Allocation Table; 3) fetching the 16-bit word
+; at this address; 4) If N was odd (so that N*1.5 was not an integer), shift
+; the word right four bits; 5) mask to 12 bits (AND with 0FFF hex).  Entry
+; number zero is used as an end-of-file trap in the OS and is passed to the
+; BIOS to help determine disk format.  Entry 1 is reserved for future use.
+; The first available allocation unit is assigned entry number two, and even
+; though it is the first, is called cluster 2.  Entries greater than 0FF8H
+; are end of file marks; entries of zero are unallocated.  Otherwise, the
+; contents of a FAT entry is the number of the next cluster in the file.
+;
+; Clusters with bad sectors are tagged with FF7H.  Any non-zero number would
+; do because these clusters show as allocated, but are not part of any
+; allocation chain and thus will never be allocated to a file.  A particular
+; number is selected so that disk checking programs know what to do (ie.  a
+; cluster with entry FF7H which is not in a chain is not an error).
+
+BREAK <DPB structure>
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+
+DIRSTRLEN       EQU     64      ; Max length in bytes of directory strings
+
+dpb     STRUC
+dpb_drive           DB      ?   ; Logical drive # assoc with DPB (A=0,B=1,...)
+dpb_UNIT            DB      ?   ; Driver unit number of DPB
+dpb_sector_size     DW      ?   ; Size of physical sector in bytes
+dpb_cluster_mask    DB      ?   ; Sectors/cluster - 1
+dpb_cluster_shift   DB      ?   ; Log2 of sectors/cluster
+dpb_first_FAT       DW      ?   ; Starting record of FATs
+dpb_FAT_count       DB      ?   ; Number of FATs for this drive
+dpb_root_entries    DW      ?   ; Number of directory entries
+dpb_first_sector    DW      ?   ; First sector of first cluster
+dpb_max_cluster     DW      ?   ; Number of clusters on drive + 1
+dpb_FAT_size        DB      ?   ; Number of records occupied by FAT
+dpb_dir_sector      DW      ?   ; Starting record of directory
+dpb_driver_addr     DD      ?   ; Pointer to driver
+dpb_media           DB      ?   ; Media byte
+dpb_first_access    DB      ?   ; This is initialized to -1 to force a media
+                                ; check the first time this DPB is used
+dpb_next_dpb        DD      ?   ; Pointer to next Drive parameter block
+dpb_current_dir     DW      ?   ; Cluster number of start of current directory
+                                ; 0 indicates root, -1 indicates invalid (disk
+                                ; ?  changed)
+dpb_dir_text        DB      DIRSTRLEN DUP(?)
+                                ; ASCIZ string of current directory
+dpb     ENDS
+
+DPBSIZ  EQU     SIZE dpb        ; Size of the structure in bytes
+
+DSKSIZ  =       dpb_max_cluster ; Size of disk (temp used during init only)
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK <File Control Block definition>
+;
+; Field definition for FCBs
+; The FCB has the following structure:
+;
+;       +---------------------------+
+;       |   Drive indicator(byte)   |
+;       +---------------------------+
+;       |    Filename (8 chars)     |
+;       +---------------------------+
+;       |    Extension (3 chars)    |
+;       +---------------------------+
+;       |   Current Extent(word)    |
+;       +---------------------------+
+;       |    Record size (word)     |
+;       +---------------------------+
+;       |    File Size (2 words)    |
+;       +---------------------------+
+;       |       Date of write       |
+;       +---------------------------+
+;       |       Time of write       |
+;       +---------------------------+
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+;       | Flags:                    |
+;       |  bit 7=0 file/1 device    |
+;       |  bit 6=0 if dirty         |
+;       |  bits 0-5 deviceid        |
+;       +---------------------------+
+;       |   first cluster in file   |
+;       +---------------------------+
+;       | position of last cluster  |
+;       +---------------------------+
+;       |   last cluster accessed   |   12 bit-+--- packed in 3 bytes
+;       +---------------------------+          |
+;       |     parent directory      |   <------+
+;       +---------------------------+
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;       |    next record number     |
+;       +---------------------------+
+;       |   random record number    |
+;       +---------------------------+
+;
+
+sys_fcb     STRUC
+fcb_drive   DB      ?
+fcb_name    DB      8 DUP (?)
+fcb_ext     DB      3 DUP (?)
+fcb_EXTENT  DW      ?
+fcb_RECSIZ  DW      ?       ; Size of record (user settable)
+fcb_FILSIZ  DW      ?       ; Size of file in bytes; used with the following
+                            ; word
+fcb_DRVBP   DW      ?       ; BP for SEARCH FIRST and SEARCH NEXT
+fcb_FDATE   DW      ?       ; Date of last writing
+fcb_FTIME   DW      ?       ; Time of last writing
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+fcb_DEVID   DB      ?       ; Device ID number, bits 0-5 if file.
+                            ; bit 7=0 for file, bit 7=1 for I/O device
+                            ; If file, bit 6=0 if dirty
+                            ; If I/O device, bit 6=0 if EOF (input)
+                            ;               Bit 5=1 if Raw mode
+                            ;               Bit 0=1 if console input device
+                            ;               Bit 1=1 if console output device
+                            ;               Bit 2=1 if null device
+                            ;               Bit 3=1 if clock device
+fcb_FIRCLUS DW      ?       ; First cluster of file
+fcb_CLUSPOS DW      ?       ; Position of last cluster accessed
+fcb_LSTCLUS DW      ?       ; Last cluster accessed and directory pack 2 12
+            DB      ?       ; bit numbers into 24 bits...
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+fcb_NR      DB      ?       ; Next record
+fcb_RR      DB      4 DUP (?)               ; Random record
+sys_fcb     ENDS
+
+FILDIRENT       = fcb_FILSIZ            ; Used only by SEARCH FIRST and SEARCH
+                                        ; NEXT
+
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+devid_file_clean        EQU     40h     ; true if file and not written
+devid_file_mask_drive   EQU     3Fh     ; mask for drive number
+
+devid_device            EQU     80h     ; true if a device
+devid_device_EOF        EQU     40h     ; true if end of file reached
+devid_device_raw        EQU     20h     ; true if in raw mode
+devid_device_special    EQU     10h     ; true if special device
+devid_device_clock      EQU     08h     ; true if clock device
+devid_device_null       EQU     04h     ; true if null device
+devid_device_con_out    EQU     02h     ; true if console output
+devid_device_con_in     EQU     01h     ; true if consle input
+
+;
+; structure of devid field as returned by IOCTL is:
+;
+;       BIT     7   6   5   4   3   2   1   0
+;             |---|---|---|---|---|---|---|---|
+;             | I | E | R | S | I | I | I | I |
+;             | S | O | A | P | S | S | S | S |
+;             | D | F | W | E | C | N | C | C |
+;             | E |   |   | C | L | U | O | I |
+;             | V |   |   | L | K | L | T | N |
+;             |---|---|---|---|---|---|---|---|
+;       ISDEV = 1 if this channel is a device
+;             = 0 if this channel is a disk file
+;
+;       If ISDEV = 1
+;
+;             EOF = 0 if End Of File on input
+;             RAW = 1 if this device is in Raw mode
+;                 = 0 if this device is cooked
+;             ISCLK = 1 if this device is the clock device
+;             ISNUL = 1 if this device is the null device
+;             ISCOT = 1 if this device is the console output
+;             ISCIN = 1 if this device is the console input
+;
+;       If ISDEV = 0
+;             EOF = 0 if channel has been written
+;             Bits 0-5  are  the  block  device  number  for
+;                 the channel (0 = A, 1 = B, ...)
+;
+devid_ISDEV     EQU     80h
+devid_EOF       EQU     40h
+devid_RAW       EQU     20h
+devid_SPECIAL   EQU     10H
+devid_ISCLK     EQU     08h
+devid_ISNUL     EQU     04h
+devid_ISCOT     EQU     02h
+devid_ISCIN     EQU     01h
+
+devid_block_dev EQU     1Fh             ; mask for block device number
+
+;
+; find first/next buffer
+;
+find_buf    STRUC
+find_buf_sattr      DB  ?           ; attribute of search
+find_buf_drive      DB  ?           ; drive of search
+find_buf_name       DB  11 DUP (?)  ; formatted name
+find_buf_LastEnt    DW  ?           ; LastEnt
+find_buf_ThisDPB    DD  ?           ; This DPB
+find_buf_DirStart   DW  ?           ; DirStart
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+find_buf_attr       DB  ?           ; attribute found
+find_buf_time       DW  ?           ; time
+find_buf_date       DW  ?           ; date
+find_buf_size_l     DW  ?           ; low(size)
+find_buf_size_h     DW  ?           ; high(size)
+find_buf_pname      DB  13 DUP (?)  ; packed name
+find_buf    ENDS
+
+BREAK <Process data block>
+;
+; Process data block (otherwise known as program header)
+;
+
+FilPerProc          EQU     20
+
+Process_data_block  STRUC
+PDB_Exit_Call       DW      ?           ; INT int_abort system terminate
+PDB_block_len       DW      ?           ; size of execution block
+                    DB      ?
+PDB_CPM_Call        DB  5 DUP (?)       ; ancient call to system
+PDB_Exit            DD      ?           ; pointer to exit routine
+PDB_Ctrl_C          DD      ?           ; pointer to ^C routine
+PDB_Fatal_abort     DD      ?           ; pointer to fatal error
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+PDB_Parent_PID      DW      ?           ; PID of parent (terminate PID)
+PDB_JFN_Table       DB  FilPerProc DUP (?)
+                                        ; indices into system table
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+PDB_environ         DW      ?           ; seg addr of environment
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+PDB_User_stack      DD      ?           ; stack of self during system calls
+PDB_PAD1            DB      1Eh DUP (?)
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+PDB_Call_system     DB      5 DUP (?)   ; portable method of system call
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+PDB_PAD2            DB      6h DUP (?)  ;
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+Process_data_block  ENDS
+
+BREAK <EXEC and EXE file structures>
+;
+; EXEC arg block - load/go program
+;
+
+;
+; The following get used as arguments to the EXEC system call.  They indicate
+; whether or not the program is executed or whether or not a program header
+; gets created.
+;
+exec_func_no_execute    EQU 1           ; no execute bit
+exec_func_overlay       EQU 2           ; overlay bit
+
+Exec0           STRUC
+Exec0_environ   DW      ?               ; seg addr of environment
+Exec0_com_line  DD      ?               ; pointer to asciz command line
+Exec0_5C_FCB    DD      ?               ; default fcb at 5C
+Exec0_6C_FCB    DD      ?               ; default fcb at 6C
+Exec0           ENDS
+
+Exec1           STRUC
+Exec1_environ   DW      ?               ; seg addr of environment
+Exec1_com_line  DD      ?               ; pointer to asciz command line
+Exec1_5C_FCB    DD      ?               ; default fcb at 5C
+Exec1_6C_FCB    DD      ?               ; default fcb at 6C
+Exec1_SP        DW      ?               ; stack pointer of program
+Exec1_SS        DW      ?               ; stack seg register of program
+Exec1_IP        DW      ?               ; entry point IP
+Exec1_CS        DW      ?               ; entry point CS
+Exec1           ENDS
+
+Exec3           STRUC
+Exec3_load_addr DW      ?               ; seg address of load point
+Exec3_reloc_fac DW      ?               ; relocation factor
+Exec3           ENDS
+
+;
+; Exit codes in upper byte
+;
+Exit_terminate      EQU     0
+Exit_abort          EQU     0
+Exit_Ctrl_C         EQU     1
+Exit_Hard_Error     EQU     2
+Exit_Keep_process   EQU     3
+
+;
+; EXE file header
+;
+
+EXE_file    STRUC
+exe_signature   DW  ?                   ; must contain 4D5A  (yay zibo!)
+exe_len_mod_512 DW  ?                   ; low 9 bits of length
+exe_pages       DW  ?                   ; number of 512b pages in file
+exe_rle_count   DW  ?                   ; count of reloc entries
+exe_par_dir     DW  ?                   ; number of paragraphs before image
+exe_min_BSS     DW  ?                   ; minimum number of para of BSS
+exe_max_BSS     DW  ?                   ; max number of para of BSS
+exe_SS          DW  ?                   ; stack of image
+exe_SP          DW  ?                   ; SP of image
+exe_chksum      DW  ?                   ; checksum  of file (ignored)
+exe_IP          DW  ?                   ; IP of entry
+exe_CS          DW  ?                   ; CS of entry
+exe_rle_table   DW  ?                   ; byte offset of reloc table
+exe_iov         DW  ?                   ; overlay number (0 for root)
+exe_sym_tab     DD  ?                   ; offset of symbol table in file
+EXE_file    ENDS
+
+exe_valid_signature     EQU 5A4Dh
+exe_valid_old_signature EQU 4D5Ah
+
+symbol_entry    STRUC
+sym_value       DD  ?
+sym_type        DW  ?
+sym_len         DB  ?
+sym_name        DB  255 dup (?)
+symbol_entry    ENDS
+
+BREAK <Internal system file table format>
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+;
+; system file table
+;
+
+sft             STRUC
+sft_link        DD      ?
+sft_count       DW      ?               ; number of entries
+sft_table       DW      ?               ; beginning of array of the following
+sft             ENDS
+
+;
+; system file table entry
+;
+
+sf_entry        STRUC
+sf_ref_count    DB      ?               ; number of processes sharing fcb
+sf_mode         DB      ?               ; mode of access
+sf_attr         DB      ?               ; attribute of file
+sf_fcb          DB      (SIZE sys_fcb) DUP (?)
+                                        ; actual FCB
+sf_entry        ENDS
+
+sf_default_number   EQU     5h
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK <Memory arena structure>
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+;
+; arena item
+;
+arena   STRUC
+arena_signature     DB  ?               ; 4D for valid item, 5A for last item
+arena_owner         DW  ?               ; owner of arena item
+arena_size          DW  ?               ; size in paragraphs of item
+arena   ENDS
+
+;
+; Current structure of the data returned by the international call
+;
+
+internat_block STRUC
+Date_tim_format DW      ?           ; 0-USA, 1-EUR, 2-JAP
+Currency_sym    DB      ?           ; Currency Symbol 5 bytes
+                DB      ?
+                DB      ?
+                DB      ?
+                DB      ?
+Thous_sep       DB      ?           ; Thousands separator 2 bytes
+                DB      ?
+Decimal_sep     DB      ?           ; Decimal separator 2 bytes
+                DB      ?
+Date_sep        DB      ?           ; Date separator 2 bytes
+                DB      ?
+Time_sep        DB      ?           ; Decimal separator 2 bytes
+                DB      ?
+Bit_feild       DB      ?           ; Bit values
+                                    ;   Bit 0 = 0 if currency symbol first
+                                    ;         = 1 if currency symbol last
+                                    ;   Bit 1 = 0 if No space after currency symbol
+                                    ;         = 1 if space after currency symbol
+Currency_cents  DB      ?           ; Number of places after currency dec point
+Time_24         DB      ?           ; 1 if 24 hour time, 0 if 12 hour time
+Map_call        DW      ?           ; Address of case mapping call (DWORD)
+                DW      ?           ; THIS IS TWO WORDS SO IT CAN BE INITIALIZED
+                                    ;  in pieces.
+Data_sep        DB      ?           ; Data list separator character
+                DB      ?
+internat_block ENDS
+
+;
+; Max size of the block returned by the INTERNATIONAL call
+;
+internat_block_max      EQU     32
+
+;
+; CAUTION: The routines in ALLOC.ASM rely on the fact that arena_signature
+; and arena_owner_system are all equal to zero and are contained in DI.  Change
+; them and change ALLOC.ASM.
+
+arena_owner_system  EQU 0               ; free block indication
+
+arena_signature_normal  EQU 4Dh         ; valid signature, not end of arena
+arena_signature_end     EQU 5Ah         ; valid signature, last block in arena
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+
+BREAK <Machine instruction definitions>
+
+mi_INT          EQU     0CDh
+mi_Long_JMP     EQU     0EAh
+mi_Long_CALL    EQU     09Ah
+mi_Long_RET     EQU     0CBh
+
+BREAK <Standard I/O assignments>
+
+stdin       EQU     0
+stdout      EQU     1
+stderr      EQU     2
+stdaux      EQU     3
+stdprn      EQU     4
+
+BREAK <Xenix subfunction assignments>
+
+open_for_read   EQU 0
+open_for_write  EQU 1
+open_for_both   EQU 2
+
+BREAK <Xenix error codes>
+
+;
+; XENIX calls all return error codes through AX.  If an error occurred then
+; the carry bit will be set and the error code is in AX.  If no error occurred
+; then the carry bit is reset and AX contains returned info.
+;
+
+no_error_occurred               EQU     0                                                              ?
+
+error_invalid_function          EQU     1
+error_file_not_found            EQU     2
+error_path_not_found            EQU     3
+error_too_many_open_files       EQU     4
+error_access_denied             EQU     5
+error_invalid_handle            EQU     6
+error_arena_trashed             EQU     7
+error_not_enough_memory         EQU     8
+error_invalid_block             EQU     9
+error_bad_environment           EQU     10
+error_bad_format                EQU     11
+error_invalid_access            EQU     12
+error_invalid_data              EQU     13
+;**** unused                    EQU     14
+error_invalid_drive             EQU     15
+error_current_directory         EQU     16
+error_not_same_device           EQU     17
+error_no_more_files             EQU     18
+
+country_not_found               EQU     error_file_not_found
+alloc_not_enough_memory         EQU     error_not_enough_memory
+alloc_arena_trashed             EQU     error_arena_trashed
+
+close_invalid_handle            EQU     error_invalid_handle
+close_invalid_function          EQU     error_invalid_function
+
+chdir_path_not_found            EQU     error_path_not_found
+
+chmod_path_not_found            EQU     error_path_not_found
+chmod_access_denied             EQU     error_access_denied
+chmod_invalid_function          EQU     error_invalid_function
+
+creat_access_denied             EQU     error_access_denied
+creat_path_not_found            EQU     error_path_not_found
+creat_too_many_open_files       EQU     error_too_many_open_files
+
+curdir_invalid_drive            EQU     error_invalid_drive
+
+dealloc_invalid_block           EQU     error_invalid_block
+dealloc_arena_trashed           EQU     error_arena_trashed
+
+dup_invalid_handle              EQU     error_invalid_handle
+dup_too_many_open_files         EQU     error_too_many_open_files
+
+dup2_invalid_handle             EQU     error_invalid_handle
+
+exec_invalid_function           EQU     error_invalid_function
+exec_bad_environment            EQU     error_bad_environment
+exec_bad_format                 EQU     error_bad_format
+exec_not_enough_memory          EQU     error_not_enough_memory
+exec_file_not_found             EQU     error_file_not_found
+
+filetimes_invalid_function      EQU     error_invalid_function
+filetimes_invalid_handle        EQU     error_invalid_handle
+
+findfirst_file_not_found        EQU     error_file_not_found
+findfirst_no_more_files         EQU     error_no_more_files
+findnext_no_more_files          EQU     error_no_more_files
+
+international_invalid_function  EQU     error_invalid_function
+
+ioctl_invalid_handle            EQU     error_invalid_handle
+ioctl_invalid_function          EQU     error_invalid_function
+ioctl_invalid_data              EQU     error_invalid_data
+
+lseek_invalid_handle            EQU     error_invalid_handle
+lseek_invalid_function          EQU     error_invalid_function
+
+mkdir_path_not_found            EQU     error_path_not_found
+mkdir_access_denied             EQU     error_access_denied
+
+open_invalid_access             EQU     error_invalid_access
+open_file_not_found             EQU     error_file_not_found
+open_access_denied              EQU     error_access_denied
+open_too_many_open_files        EQU     error_too_many_open_files
+
+read_invalid_handle             EQU     error_invalid_handle
+read_access_denied              EQU     error_access_denied
+
+rename_file_not_found           EQU     error_file_not_found
+rename_not_same_device          EQU     error_not_same_device
+rename_access_denied            EQU     error_access_denied
+
+rmdir_path_not_found            EQU     error_path_not_found
+rmdir_access_denied             EQU     error_access_denied
+rmdir_current_directory         EQU     error_current_directory
+
+setblock_invalid_block          EQU     error_invalid_block
+setblock_arena_trashed          EQU     error_arena_trashed
+setblock_not_enough_memory      EQU     error_not_enough_memory
+setblock_invalid_function       EQU     error_invalid_function
+
+unlink_file_not_found           EQU     error_file_not_found
+unlink_access_denied            EQU     error_access_denied
+
+write_invalid_handle            EQU     error_invalid_handle
+write_access_denied             EQU     error_access_denied
+
+BREAK <system call definitions>
+
+Abort                           EQU 0   ;  0      0
+Std_Con_Input                   EQU 1   ;  1      1
+Std_Con_Output                  EQU 2   ;  2      2
+Std_Aux_Input                   EQU 3   ;  3      3
+Std_Aux_Output                  EQU 4   ;  4      4
+Std_Printer_Output              EQU 5   ;  5      5
+Raw_Con_IO                      EQU 6   ;  6      6
+Raw_Con_Input                   EQU 7   ;  7      7
+Std_Con_Input_No_Echo           EQU 8   ;  8      8
+Std_Con_String_Output           EQU 9   ;  9      9
+Std_Con_String_Input            EQU 10  ; 10      A
+Std_Con_Input_Status            EQU 11  ; 11      B
+Std_Con_Input_Flush             EQU 12  ; 12      C
+Disk_Reset                      EQU 13  ; 13      D
+Set_Default_Drive               EQU 14  ; 14      E
+FCB_Open                        EQU 15  ; 15      F
+FCB_Close                       EQU 16  ; 16     10
+Dir_Search_First                EQU 17  ; 17     11
+Dir_Search_Next                 EQU 18  ; 18     12
+FCB_Delete                      EQU 19  ; 19     13
+FCB_Seq_Read                    EQU 20  ; 20     14
+FCB_Seq_Write                   EQU 21  ; 21     15
+FCB_Create                      EQU 22  ; 22     16
+FCB_Rename                      EQU 23  ; 23     17
+Get_Default_Drive               EQU 25  ; 25     19
+Set_DMA                         EQU 26  ; 26     1A
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+Get_Default_DPB                 EQU 31  ; 31     1F
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+FCB_Random_Read                 EQU 33  ; 33     21
+FCB_Random_Write                EQU 34  ; 34     22
+Get_FCB_File_Length             EQU 35  ; 35     23
+Get_FCB_Position                EQU 36  ; 36     24
+Set_Interrupt_Vector            EQU 37  ; 37     25
+Create_Process_Data_Block       EQU 38  ; 38     26
+FCB_Random_Read_Block           EQU 39  ; 39     27
+FCB_Random_Write_Block          EQU 40  ; 40     28
+Parse_File_Descriptor           EQU 41  ; 41     29
+Get_Date                        EQU 42  ; 42     2A
+Set_Date                        EQU 43  ; 43     2B
+Get_Time                        EQU 44  ; 44     2C
+Set_Time                        EQU 45  ; 45     2D
+Set_Verify_On_Write             EQU 46  ; 46     2E
+; Extended functionality group
+Get_DMA                         EQU 47  ; 47     2F
+Get_Version                     EQU 48  ; 48     30
+Keep_Process                    EQU 49  ; 49     31
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+Get_DPB                         EQU 50  ; 50     32
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+Set_CTRL_C_Trapping             EQU 51  ; 51     33
+Get_InDOS_Flag                  EQU 52  ; 52     34
+Get_Interrupt_Vector            EQU 53  ; 53     35
+Get_Drive_Freespace             EQU 54  ; 54     36
+Char_Oper                       EQU 55  ; 55     37
+International                   EQU 56  ; 56     38
+;   Directory Group
+MKDir                           EQU 57  ; 57     39
+RMDir                           EQU 58  ; 58     3A
+CHDir                           EQU 59  ; 59     3B
+;   File Group
+Creat                           EQU 60  ; 60     3C
+Open                            EQU 61  ; 61     3D
+Close                           EQU 62  ; 62     3E
+Read                            EQU 63  ; 63     3F
+Write                           EQU 64  ; 64     40
+Unlink                          EQU 65  ; 65     41
+LSeek                           EQU 66  ; 66     42
+CHMod                           EQU 67  ; 67     43
+IOCtl                           EQU 68  ; 68     44
+XDup                            EQU 69  ; 69     45
+XDup2                           EQU 70  ; 70     46
+Current_Dir                     EQU 71  ; 71     47
+;    Memory Group
+Alloc                           EQU 72  ; 72     48
+Dealloc                         EQU 73  ; 73     49
+Setblock                        EQU 74  ; 74     4A
+;    Process Group
+Exec                            EQU 75  ; 75     4B
+Exit                            EQU 76  ; 76     4C
+Wait                            EQU 77  ; 77     4D
+Find_First                      EQU 78  ; 78     4E
+;   Special Group
+Find_Next                       EQU 79  ; 79     4F
+; SPECIAL SYSTEM GROUP
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+Set_Current_PDB                 EQU 80  ; 80     50
+Get_Current_PDB                 EQU 81  ; 81     51
+Get_In_Vars                     EQU 82  ; 82     52
+SetDPB                          EQU 83  ; 83     53
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+Get_Verify_On_Write             EQU 84  ; 84     54
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;                                                                          ;
+Dup_PDB                         EQU 85  ; 85     55
+;                                                                          ;
+;            C  A  V  E  A  T     P  R  O  G  R  A  M  M  E  R             ;
+;----+----+----+----+----+----+----+----+----+----+----+----+----+----+----;
+Rename                          EQU 86  ; 86     56
+File_Times                      EQU 87  ; 87     57
+AllocOper                       EQU 88  ; 88     58
+; Network extention system calls
+GetExtendedError                EQU 89  ; 89     59
+CreateTempFile                  EQU 90  ; 90     5A
+CreateNewFile                   EQU 91  ; 91     5B
+LockOper                        EQU 92  ; 92     5C Lock and Unlock
+ServerCall                      EQU 93  ; 93     5D CommitAll, ServerDOSCall,
+                                        ;           CloseByName, CloseUser,
+                                        ;           CloseUserProcess,
+                                        ;           GetOpenFileList
+UserIDOper                      EQU 94  ; 94     5E Get and Set
+AssignOper                      EQU 95  ; 95     5F On, Off, Get, Set, Cancel
+
+Set_Oem_Handler                 EQU 248 ; 248    F8
+OEM_C1                          EQU 249 ; 249    F9
+OEM_C2                          EQU 250 ; 250    FA
+OEM_C3                          EQU 251 ; 251    FB
+OEM_C4                          EQU 252 ; 252    FC
+OEM_C5                          EQU 253 ; 253    FD
+OEM_C6                          EQU 254 ; 254    FE
+OEM_C7                          EQU 255 ; 255    FF
+SUBTTL