ecm 2026-04i

source/Interrupt List/INT 21 DOS Function Calls/INT 2126 DOS 1 CREATE NEW PROGRAM SEGMENT PREFIX.txt

@@ -40,6 +40,7 @@ Offset	Size	Description	(Table 01378)
  12h	DWORD	DOS 1.1+ stored INT 24 critical error handler address
  16h	WORD	segment of parent PSP (can be this PSP itself)
  18h 20 BYTEs	DOS 2+ Job File Table, one byte per file handle, FFh = closed
+		(the JFT is known as Process Handle Table for lDOS)
  2Ch	WORD	DOS 2+ segment of environment for process (see #01379)
  2Eh	DWORD	DOS 2+ process's SS:SP on entry to last INT 21 call
  32h	WORD	DOS 3+ number of entries in JFT (default 20)

source/Interrupt List/INT 21 DOS Function Calls/INT 2152 DOS 2 internal SYSVARS GET LIST OF LISTS.txt

@@ -507,7 +507,7 @@ Offset	Size	Description	(Table 01639)
 	 20h	WORD	absolute cluster number of current cluster
 	 22h	WORD	???
 	 24h	DWORD	current file position???
-SeeAlso: #01640,#01641,#01642
+SeeAlso: #01640,#01641,#01642,#26003,#26004,#26005
 
 Format of DOS 3.0 system file tables and FCB tables:
 Offset	Size	Description	(Table 01640)
@@ -526,7 +526,7 @@ Offset	Size	Description	(Table 01640)
 			  AUX/CON/PRN contain segment of IO.SYS startup code)
 	 34h	WORD	(SHARE.EXE) offset in SHARE code seg of share record
 	 36h	WORD	??? apparently always 0000h
-SeeAlso: #01639,#01641,#01642
+SeeAlso: #01639,#01641,#01642,#26003,#26004,#26005
 
 Format of DOS 3.1-3.3x, DR DOS 5.0-6.0 system file tables and FCB tables:
 Offset	Size	Description	(Table 01641)
@@ -577,9 +577,9 @@ Offset	Size	Description	(Table 01641)
 			  of IO.SYS startup code)
 	 33h	WORD	offset within SHARE.EXE code segment of
 			  sharing record (see #01637) 0000h = none
-SeeAlso: #01639,#01640,#01642
+SeeAlso: #01639,#01640,#01642,#26003,#26004,#26005
 
-Format of DOS 4.0-6.0 system file tables and FCB tables:
+Format of MS-DOS v4.00 to v6.22 system file tables and FCB tables:
 Offset	Size	Description	(Table 01642)
  00h	DWORD	pointer to next file table (offset FFFFh if last)
  04h	WORD	number of files in this table
@@ -602,8 +602,6 @@ Offset	Size	Description	(Table 01642)
 			else pointer to DOS Drive Parameter Block
 			  (see #01395 at AH=32h) or REDIR data
 	 0Bh	WORD	starting cluster of file (local files only)
-			not set for FAT32-capable versions of Windows95
-			  (since they allow 32-bit cluster numbers)
 	 0Dh	WORD	file time in packed format (see #01665)
 	 0Fh	WORD	file date in packed format (see #01666)
 	 11h	DWORD	file size
@@ -630,10 +628,199 @@ Offset	Size	Description	(Table 01642)
 	 35h	WORD	(local) absolute cluster number of last clustr accessed
 			(redirector) ???
 	 37h	DWORD	pointer to IFS driver for file, 0000000h if native DOS
-Note:	the OS/2 2.0 DOS Boot Session does not properly fill in the filename
+Notes:	the OS/2 2.0 DOS Boot Session does not properly fill in the filename
 	  field due to incomplete support for SFTs; the OS/2 2.0 DOS Window
 	  does not appear to support SFTs at all
-SeeAlso: #01639,#01640,#01641
+	the first SFT container at DOSDATA:00CCh contains 5 entries
+SeeAlso: #01639,#01640,#01641,#26003,#26004,#26005
+
+Format of MS-DOS v7.10 and FAT32 FreeDOS system file tables and FCB tables:
+Offset	Size	Description	(Table 26003)
+ 00h	DWORD	pointer to next file table (offset FFFFh if last)
+ 04h	WORD	number of files in this table
+ 06h  3Bh bytes per file
+	Offset	Size	Description
+	 00h	WORD	number of file handles referring to this file
+			FFFFh if in use but not referenced (the FFFFh busy
+			  marker is not used by FreeDOS)
+	 02h	WORD	file open mode (see AX=6C00h,#01402 at AH=3Dh)
+			bit 15 set if this file opened via FCB
+	 04h	BYTE	file attribute (see #01420 at AX=4301h)
+	 05h	WORD	device info word (see also #01423 at AX=4400h)
+			bit 15 set if remote file
+			bit 14 set means do not set file date/time on closing
+			bit 13 set if named pipe
+			bit 12 set if no inherit
+			bit 11 set if network spooler
+			bit 7  set if device, clear if file (only if local)
+			bits 6-0 as for AX=4400h
+	 07h	DWORD	pointer to device driver header if character device
+			else pointer to DOS Drive Parameter Block
+			  (see #01395 at AH=32h) or REDIR data
+	 0Bh	WORD	high part of relative cluster within file
+	 0Dh	WORD	file time in packed format (see #01665)
+	 0Fh	WORD	file date in packed format (see #01666)
+	 11h	DWORD	file size
+	 15h	DWORD	current offset in file (SFT)
+			LRU counters (FCB table, two WORDs)
+	---local file---
+	 19h	WORD	low part of relative cluster within file
+	 1Bh	DWORD	number of sector containing directory entry
+	 1Fh	BYTE	number of dir entry within sector (byte offset/32)
+	---network redirector---
+	 19h	DWORD	pointer to REDIRIFS record
+	 1Dh  3 BYTEs	???
+	------
+	 20h 11 BYTEs	filename in FCB format (no path/period, blank-padded)
+	 2Bh	DWORD	starting cluster of file
+	 2Fh	WORD	(SHARE.EXE) network machine number which opened file
+			(Windows Enhanced mode DOSMGR uses the virtual machine
+			  ID as the machine number; see INT 2F/AX=1683h)
+	 31h	WORD	PSP segment of file's owner (see #01378 at AH=26h)
+			  (first three entries for AUX/CON/PRN contain segment
+			  of IO.SYS startup code)
+	 33h	WORD	offset within SHARE.EXE code segment of
+			sharing record (see #01595)  0000h = none
+	 35h	DWORD	absolute cluster number of last cluster accessed
+	 39h	WORD	padding
+Notes:	start cluster of MS-DOS v6 at offset 0Bh is now high part of the
+	  relative cluster in file
+	sharer pointer to next SFT in MS-DOS v6 is now file start cluster
+	low word of IFS pointer in MS-DOS v6 is now high word of absolute
+	  cluster number in file
+	MS-DOS v7.10 and FreeDOS use directory entry sector, not cluster
+	the first SFT container at DOSDATA:00CCh contains 5 entries
+SeeAlso: #01639,#01640,#01641,#01642,#26005
+
+Format of FAT32 and FAT+ enabled build of Enhanced DR-DOS v7.01.08
+  (including lDOS flavour) system file tables and FCB tables:
+Offset	Size	Description	(Table 26004)
+ 00h	DWORD	pointer to next file table (offset FFFFh if last)
+ 04h	WORD	number of files in this table
+ 06h  4Bh bytes per file
+	Offset	Size	Description
+	 00h	WORD	number of file handles referring to this file
+			FFFFh if in use but not referenced
+	 02h	WORD	file open mode (see AX=6C00h,#01402 at AH=3Dh)
+			bit 15 set if this file opened via FCB
+	 04h	BYTE	file attribute (see #01420 at AX=4301h)
+	 05h	WORD	device info word (see also #01423 at AX=4400h)
+			bit 15 set if remote file
+			bit 14 set means do not set file date/time on closing
+			bit 13 set if named pipe
+			bit 12 set if no inherit
+			bit 11 set if network spooler
+			bit 7  set if device, clear if file (only if local)
+			bits 6-0 as for AX=4400h
+	 07h	DWORD	pointer to device driver header if character device
+			else pointer to DOS Drive Parameter Block
+			  (see #01395 at AH=32h) or REDIR data
+	 0Bh	WORD	low word of starting cluster of file
+	 0Dh	WORD	file time in packed format (see #01665)
+	 0Fh	WORD	file date in packed format (see #01666)
+	 11h	DWORD	low dword of file size
+	 15h	DWORD	low dword of current offset in file (SFT)
+			LRU counters (FCB table, two WORDs)
+	---local file---
+	 19h	WORD	low word of relative cluster within file
+	 1Bh	WORD	low word of cluster number of directory entry
+	 1Dh	BYTE	padding
+	 1Eh	BYTE	high byte of dir entry number within cluster
+	 1Fh	BYTE	low byte of dir entry number within cluster (byte offset/32)
+	---network redirector---
+	 19h	DWORD	pointer to REDIRIFS record
+	 1Dh  3 BYTEs	???
+	------
+	 20h 11 BYTEs	filename in FCB format (no path/period, blank-padded)
+	 2Bh	DWORD	(SHARE.EXE) pointer to previous SFT sharing same file
+	 2Fh	WORD	(SHARE.EXE) network machine number which opened file
+			(Windows Enhanced mode DOSMGR uses the virtual machine
+			  ID as the machine number; see INT 2F/AX=1683h)
+	 31h	WORD	PSP segment of file's owner (see #01378 at AH=26h)
+			  (first three entries for AUX/CON/PRN contain segment
+			  of IO.SYS startup code)
+	 33h	WORD	offset within SHARE.EXE code segment of
+			sharing record (see #01595)  0000h = none
+	 35h	WORD	low word of absolute cluster number of last cluster
+			  accessed
+	 37h	DWORD	pointer to IFS driver for file, 0000000h if native DOS
+	 3Bh	WORD	high word of first cluster in file
+	 3Dh	WORD	high word of relative cluster within file
+	 3Fh	WORD	high word of cluster number of directory entry
+	 41h	WORD	high word of absolute cluster number of last cluster
+			  accessed
+	 43h	DWORD	high dword of file size
+	 47h	DWORD	high dword of current offset in file
+Notes:	EDR-DOS builds with this SFT layout only contain 3 SFT entries
+	  at DOSDATA:00CCh rather than 5 entries.
+SeeAlso: #01639,#01640,#01641,#01642,#26005
+
+Format of SvarDOS flavour Enhanced DR-DOS system file tables and FCB tables:
+Offset	Size	Description	(Table 26005)
+ 00h	DWORD	pointer to next file table (offset FFFFh if last)
+ 04h	WORD	number of files in this table
+ 06h  3Bh bytes per file (no FAT+) or 42h bytes per file (with FAT+)
+	Offset	Size	Description
+	 00h	WORD	number of file handles referring to this file
+			FFFFh if in use but not referenced
+	 02h	WORD	file open mode (see AX=6C00h,#01402 at AH=3Dh)
+			bit 15 set if this file opened via FCB
+	 04h	BYTE	file attribute (see #01420 at AX=4301h)
+	 05h	WORD	device info word (see also #01423 at AX=4400h)
+			bit 15 set if remote file
+			bit 14 set means do not set file date/time on closing
+			bit 13 set if named pipe
+			bit 12 set if no inherit
+			bit 11 set if network spooler
+			bit 7  set if device, clear if file (only if local)
+			bits 6-0 as for AX=4400h
+	 07h	DWORD	pointer to device driver header if character device
+			else pointer to DOS Drive Parameter Block
+			  (see #01395 at AH=32h) or REDIR data
+	 0Bh	WORD	high part of relative cluster within file
+	 0Dh	WORD	file time in packed format (see #01665)
+	 0Fh	WORD	file date in packed format (see #01666)
+	 11h	DWORD	file size
+	 15h	DWORD	current offset in file (SFT)
+			LRU counters (FCB table, two WORDs)
+	---local file---
+	 19h	WORD	low part of relative cluster within file
+	 1Bh	DWORD	cluster containing directory entry
+	 1Fh	BYTE	low byte of number of dir entry within cluster
+	---network redirector---
+	 19h	DWORD	pointer to REDIRIFS record
+	 1Dh  3 BYTEs	???
+	------
+	 20h 11 BYTEs	filename in FCB format (no path/period, blank-padded)
+	 2Bh	DWORD	starting cluster of file
+	 2Fh	WORD	(SHARE.EXE) network machine number which opened file
+			(Windows Enhanced mode DOSMGR uses the virtual machine
+			  ID as the machine number; see INT 2F/AX=1683h)
+	 31h	WORD	PSP segment of file's owner (see #01378 at AH=26h)
+			  (first three entries for AUX/CON/PRN contain segment
+			  of IO.SYS startup code)
+	 33h	WORD	offset within SHARE.EXE code segment of
+			sharing record (see #01595)  0000h = none
+	 35h	DWORD	absolute cluster number of last cluster accessed
+	 39h	BYTE	high byte of number of dir entry within cluster
+	--- no FAT+ ---
+	 3Ah	BYTE	padding
+	--- with FAT+ ---
+	 3Ah	DWORD	high dword of file size
+	 3Eh	DWORD	high dword of current offset in file
+Notes:	start cluster of MS-DOS v6 at offset 0Bh is now high part of the
+	  relative cluster in file
+	sharer pointer to next SFT in MS-DOS v6 is now file start cluster
+	low word of IFS pointer in MS-DOS v6 is now high word of absolute
+	  cluster number in file
+	SvarDOS flavour EDR-DOS uses a directory cluster, and places the
+	  needed high byte of the directory entry in the otherwise unused
+	  padding near the end.
+	SvarDOS flavour builds allow disabling FAT+ support in which case
+	  the high dwords are absent, instead there is 1 byte of padding.
+	EDR-DOS builds with the SvarDOS FAT+ SFT layout only contain 4
+	  SFT entries at DOSDATA:00CCh rather than 5 entries.
+SeeAlso: #01639,#01640,#01641,#01642,#26003,#26004
 
 Format of current directory structure (CDS) (array, LASTDRIVE entries):
 Offset	Size	Description	(Table 01643)

source/Interrupt List/INT 2F Multiplex/Networking/INT 2F1116 NETWORK REDIRECTOR OPEN EXISTING REMOTE FILE.txt

@@ -15,7 +15,23 @@ Return: CF set on error
 	CF clear if successful
 	    SFT filled (except handle count, which DOS manages itself)
 	STACK unchanged
-Note:	this function is called by the DOS 3.1+ kernel
+Notes:	this function is called by the DOS 3.1+ kernel
+	in MS-DOS, lDOS, and Enhanced DR-DOS the handle count is FFFFh
+	  during this call, marking the SFT as "busy". they all
+	  unconditionally set the count to 0001h after successful open.
+	MS-DOS v5+ and lDOS will free "busy" SFTs belonging to the
+	  active process (matching process ID and machine ID) during
+	  process termination if the process isn't self-parented and the
+	  termination is not TSR.
+	MS-DOS v4 and Enhanced DR-DOS will free any SFTs belonging to
+	  the active process (matching process ID and machine ID) during
+	  process termination if the process isn't self-parented and the
+	  termination is not TSR.
+	FreeDOS seems to pass the SFT with a handle count of 0000h, and
+	  increments it if it is still 0000h after successful open. it
+	  doesn't seem to close SFTs like the MS-DOS v5 "busy" SFTs as
+	  associated with a process (only closing the handles found in
+	  the PHT / Job File Table and SFTs in use for FCBs).
 SeeAlso: AX=1106h,AX=1115h,AX=1117h,AX=1118h,AX=112Eh,INT 21/AH=3Dh
 SeeAlso: INT 21/AH=60h
-
+

source/Interrupt List/INT 2F Multiplex/Networking/INT 2F1117 NETWORK REDIRECTOR CREATETRUNCATE REMOTE FILE.txt

@@ -18,6 +18,23 @@ Return: CF set on error
 	CF clear if successful
 	    SFT filled (except handle count, which DOS manages itself)
 	STACK unchanged
-Note:	this function is called by the DOS 3.1+ kernel
+Notes:	this function is called by the DOS 3.1+ kernel
+	in MS-DOS, lDOS, and Enhanced DR-DOS the handle count is FFFFh
+	  during this call, marking the SFT as "busy". they all
+	  unconditionally set the count to 0001h after successful open.
+	MS-DOS v5+ and lDOS will free "busy" SFTs belonging to the
+	  active process (matching process ID and machine ID) during
+	  process termination if the process isn't self-parented and the
+	  termination is not TSR.
+	MS-DOS v4 and Enhanced DR-DOS will free any SFTs belonging to
+	  the active process (matching process ID and machine ID) during
+	  process termination if the process isn't self-parented and the
+	  termination is not TSR.
+	FreeDOS seems to pass the SFT with a handle count of 0000h, and
+	  increments it if it is still 0000h after successful open. it
+	  doesn't seem to close SFTs like the MS-DOS v5 "busy" SFTs as
+	  associated with a process (only closing the handles found in
+	  the PHT / Job File Table and SFTs in use for FCBs).
 SeeAlso: AX=1106h,AX=1116h,AX=1118h,AX=112Eh,INT 21/AH=3Ch,INT 21/AH=60h
-
+
+

source/Interrupt List/INT 2F Multiplex/Networking/INT 2F111D NETWORK REDIRECTOR CLOSE ALL REMOTE FILES FOR PROCESS ABORT.txt

@@ -13,5 +13,9 @@ Notes:	used when a process is aborted; the process being terminated is
 	  indicated by the "sharing PSP" field in the SDA (offset 1Ah/1Ch)
 	this function is called by the DOS 3.1+ kernel
 	closes all FCBs opened by process
+	this is only called if the process being terminated isn't self-
+	  parented and the termination is no TSR.
+	called after all PHT / Job File Table entries have been closed,
+	  and before FCB SFTs and busy SFTs are freed.
 SeeAlso: INT 21/AX=5D04h
-
+

source/Interrupt List/INT 2F Multiplex/Networking/INT 2F1122 NETWORK REDIRECTOR PROCESS TERMINATION HOOK.txt

@@ -10,6 +10,9 @@ INT 2F CU - NETWORK REDIRECTOR - PROCESS TERMINATION HOOK
 	DS = PSP of process about to terminate
 Return: ???
 Notes:	this function is called by the DOS 3.1+ kernel
+	this function is always called during termination, even if
+	  the process is self-parented or the termination is TSR
 	after calling this function, the kernel calls INT 2F/AX=111Dh
+	  (if it is called at all, not for self-parented or TSR)
 SeeAlso: AX=111Dh,INT 21/AH=4Ch,INT 60/DI=0601h
-
+

source/Interrupt List/INT 2F Multiplex/Networking/INT 2F112E NETWORK REDIRECTOR DOS 40 EXTENDED OPENCREATE FILE.txt

@@ -23,11 +23,27 @@ Return: CF set on error
 		02h file created
 		03h file replaced (truncated)
 	    SFT initialized (except handle count, which DOS manages itself)
-Note:	this function is called by the DOS 4.0+ kernel
-BUG:	this function is not called correctly under some DOS versions
+Notes:	this function is called by the DOS 4.0+ kernel
+	in MS-DOS, lDOS, and Enhanced DR-DOS the handle count is FFFFh
+	  during this call, marking the SFT as "busy". they all
+	  unconditionally set the count to 0001h after successful open.
+	MS-DOS v5+ and lDOS will free "busy" SFTs belonging to the
+	  active process (matching process ID and machine ID) during
+	  process termination if the process isn't self-parented and the
+	  termination is not TSR.
+	MS-DOS v4 and Enhanced DR-DOS will free any SFTs belonging to
+	  the active process (matching process ID and machine ID) during
+	  process termination if the process isn't self-parented and the
+	  termination is not TSR.
+	FreeDOS seems to pass the SFT with a handle count of 0000h, and
+	  increments it if it is still 0000h after successful open. it
+	  doesn't seem to close SFTs like the MS-DOS v5 "busy" SFTs as
+	  associated with a process (only closing the handles found in
+	  the PHT / Job File Table and SFTs in use for FCBs).
+BUGS:	this function is not called correctly under some DOS versions
 	  (at least 5.0 and 6.2):
 	    the file attribute on the stack is not correct if the action
 	      code is 11h,
 	    the result code in CX is not passed back to the application.
 SeeAlso: AX=1115h,AX=1116h,AX=1117h,INT 21/AX=6C00h
-
+