Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!rutgers!nysernic!itsgw!batcomputer!pyramid!voder!kontron!cramer From: cramer@kontron.UUCP (Clayton Cramer) Newsgroups: comp.lang.c Subject: Re: Assembly langauge subroutines for use with C Message-ID: <1731@kontron.UUCP> Date: Tue, 21-Jul-87 13:33:31 EDT Article-I.D.: kontron.1731 Posted: Tue Jul 21 13:33:31 1987 Date-Received: Thu, 23-Jul-87 04:43:20 EDT References: <3647@watdcsu.waterloo.edu> Distribution: na Organization: Kontron Electronics, Mt. View, CA Lines: 16 > How does one go about writing an assembly function that can be linked > and used by a C program? I have tried several times to get my modules > to link properly but with the end result of "Unresolved external". > I have prefaced the function name with an underscore and I still can't > manage to get my C code to realize that yes, there is an assembly function > by that name in one of the linked modules. HELP! > I'm using MSC 4.0 on an IBM-PC AT. > > Steve Ryder, Independent Studies, University of Waterloo The underscore on the function name is necessary, but consider the case. MASM folds all names to uppercase in the symbol table unless you use the /MX option. If your assembler subroutine is named "_foo", and you call it as "FOO" from C, it will work. Clayton E>+ >+ >/B