craig@mstr.hgc.edu (craig chaiken) (10/11/90)
A recent PC Magazine article by Ray Duncan indicated that MSDOS 3.x has the undocumented network hooks, or network redirection functions. These function supposedly permit important LAN software products by companies such as Novell, Microsoft, and IBM to transparently access files on non-FAT based (non-DOS compatible) file systems. *** Warning, this part gets technical *** By tracing through the IBMDOS.COM, I was able to determine that all disk related INT 21H calls hook into INT 2FH, passing 11H in AH and 00H through 26H in AL. The values in AL seem to correspond to disk related INT 21H calls. The CPU registers used by INT 2FH are very different from the ones used by INT 21H. Without documentation, using INT 2FH will require many hours of reverse engineering. My question is, "Does anyone have any documentation describing how parameters are passed to and from the network redirector, INT 2FH function 11H?" I will post any information that I receive. Craig Chaiken (Author of M&T Books' "Blueprint of a LAN") craig@mstr.hgc.edu
torre@msa3b.UUCP (Patrick Torre) (10/11/90)
craig@mstr.hgc.edu (craig chaiken) writes: >My question is, "Does anyone have any documentation describing how >parameters are passed to and from the network redirector, INT 2FH >function 11H?" I will post any information that I receive. >Craig Chaiken (Author of M&T Books' "Blueprint of a LAN") >craig@mstr.hgc.edu The second edition of the DOS PROGRAMMER'S REFERENCE (QUE Programming series) contains good documentation of these and other "undocumented" interupts and functions. Make sure you look at the second edition, the first was not worth buying. from the book - "Int 2Fh Multiplex Service Interrupt Multiplex service, only partially documented. Controlled by content of AH register at entry, which may range from 01 through FFh. Comments: Only Function 12h, DOS internal services, is present in "vanilla" DOS operation; additional functions graft themselves into this service when the corresponding program is installed. For example, Function 01 has no meaning unless the resident portion of the DOS print spooler (PRINT.COM) has been installed." etc, etc.... there are functions for assorted I/O and other utility functions: Function 12h Subfunction 05h - output a character Function 12h Subfunction 04h - normalize path separator Function 12h Subfunction 07h - move disk buffer Function 12h Subfunction 0Ch - IOCTL open used by DOS It is definatly a book worth having. Just my opinion - I am in no way associated with the publisher. -- Patrick Torre @ Dun and Bradstreet Software, Inc (404) 239-2061 {emory,gatech}!nanovx!msa3b!torre
nelson@sun.soe.clarkson.edu (Russ Nelson) (10/12/90)
In article <1409@msa3b.UUCP> torre@msa3b.UUCP (Patrick Torre) writes: craig@mstr.hgc.edu (craig chaiken) writes: >My question is, "Does anyone have any documentation describing how >parameters are passed to and from the network redirector, INT 2FH >function 11H?" I will post any information that I receive. The second edition of the DOS PROGRAMMER'S REFERENCE (QUE Programming series) contains good documentation of these and other "undocumented" interupts and functions. Isn't that the book that took an outdated copy of Ralf Brown's Interrupt List and printed it up verbatim? -- --russ (nelson@clutx [.bitnet | .clarkson.edu]) Russ.Nelson@$315.268.6667 It's better to get mugged than to live a life of fear -- Freeman Dyson
Ralf.Brown@B.GP.CS.CMU.EDU (10/12/90)
In article <NELSON.90Oct11230857@image.clarkson.edu>, nelson@sun.soe.clarkson.edu (Russ Nelson) wrote: }In article <1409@msa3b.UUCP> torre@msa3b.UUCP (Patrick Torre) writes: } The second edition of the DOS PROGRAMMER'S REFERENCE } (QUE Programming series) } contains good documentation of these and other "undocumented" } interupts and functions. } }Isn't that the book that took an outdated copy of Ralf Brown's Interrupt List }and printed it up verbatim? I saw it in a store about a year ago (may have been first edition) and flipped through it. It wasn't a verbatim copy of the entire list, but some of the undocumented calls (such as INT 21/AH=52h get list-of-lists) were included verbatim except for changing "???" to "unknown". -- UUCP: {ucbvax,harvard}!cs.cmu.edu!ralf -=- 412-268-3053 (school) -=- FAX: ask ARPA: ralf@cs.cmu.edu BIT: ralf%cs.cmu.edu@CMUCCVMA FIDO: 1:129/3.1 Disclaimer? | I was gratified to be able to answer promptly, and I did. What's that? | I said I didn't know. --Mark Twain
louie@cellar.bae.bellcore.com (Paul Louie) (10/16/90)
In article <584@mstr.hgc.edu> craig@mstr.hgc.edu (craig chaiken) writes: >My question is, "Does anyone have any documentation describing how >parameters are passed to and from the network redirector, INT 2FH >function 11H?" I will post any information that I receive. I am impressed by your determination and ability in tracing through IBMDOS.COM in the attempt of learning INT 2FH. The information you're looking for is available through Novell. When you registered with them as an Independent Developer you get technical newsletters covering various network topics. Also, if you purchase their C-Libraries these topic is covered also.