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Xref: sserve comp.unix.questions:33729 comp.unix.wizards:29335 comp.unix.internals:5758 comp.unix.bsd:11940 comp.sys.3b1:5611 alt.folklore.computers:36292 Newsgroups: comp.unix.questions,comp.unix.wizards,comp.unix.internals,comp.unix.bsd,comp.sys.3b1,alt.folklore.computers Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!howland.reston.ans.net!zaphod.mps.ohio-state.edu!ub!galileo.cc.rochester.edu!rochester!rit!isc-newsserver!ultb!nmw1638 From: nmw1638@ultb.isc.rit.edu (N.M. Williams) Subject: I need info on line discipline programming Message-ID: <1993Apr29.192653.8006@ultb.isc.rit.edu> Sender: news@ultb.isc.rit.edu (USENET News System) Nntp-Posting-Host: ultb-gw.isc.rit.edu Reply-To: nmw1638@ultb.rit.edu () Organization: Rochester Institute of Technology Date: Thu, 29 Apr 1993 19:26:53 GMT Lines: 55 [Note cross-posting] Hi, I need information on how line disciplines interact with tty drivers and the kernel in SVR3.x. I include here a copy of the linesw definition in <sys/conf.h>. Any help would be greatly appreciated. (BTW, I have a 3b1 running SVR3.51m, this is the target system). ******<sys/conf.h> extract********* #include <sys/types.h> #include <sys/iobuf.h> /* * Line discipline switch. */ struct linesw { int (*l_open)(); int (*l_close)(); int (*l_read)(); int (*l_write)(); int (*l_ioctl)(); int (*l_input)(); int (*l_output)(); int (*l_mdmint)(); }; extern struct linesw linesw[]; extern int (*ldmisc[])(); extern int linecnt; ******end conf.h extract***** From what I know so far every tty driver on my sys uses the line discipline linesw[0]; a PD/free package implements select(2) on this system by preempting linesw[0].l_input, it checks some stuff, calls some select(2) related routines if necessary, and then returns control to the original l_input function. I have some projects for which I would need to know how the functions in linesw interact with the drivers and with the kernel so I can program my own. Again, I would really appreciate any pointers, anything on this stuff, thanks in advance, Nick -- ______ E-mail: nmw1638@cs.rit.edu nmw1638@ultb.isc.rit.edu \ \/ / Snail Mail: CPU 645, 25 Andrews Memorial Dr, Rochester, NY 14623 \/\/ DOSophobic, VMSophobic, UNIXphile (exAMIGAphile). Standard Disclaimers apply.