2.3 What's What in src

When we describe building sendmail, we will refer to the source directory by the name src. That directory is the same as the src directory that is shown when you list the distribution directory:

% cd sendmail-8.8.4
% ls
FAQ             RELEASE_NOTES   mail.local      rmail
KNOWNBUGS       cf              mailstats       smrsh
Makefile        contrib         makemap         src            note
READ_ME         doc             praliases       test

Change into the src directory and look at what is there:

% cd src
% ls
Makefile        collect.c       mailq.0         pathnames.h     stats.c
Makefiles       conf.c          mailq.1         queue.c         sysexits.c
READ_ME         conf.h          mailstats.h     readcf.c        sysexits.h
TRACEFLAGS      convtime.c      main.c          recipient.c     trace.c
alias.c         daemon.c        makesendmail    savemail.c      udb.c
aliases         deliver.c       map.c           sendmail.0      useful.h
aliases.0       domain.c        mci.c           sendmail.8      usersmtp.c
aliases.5       envelope.c      mime.c          sendmail.h      util.c
arpadate.c      err.c           newaliases.0    sendmail.hf     version.c
cdefs.h         headers.c       newaliases.1    srvrsmtp.c
clock.c         macro.c         parseaddr.c     stab.c

The files whose names end in .0 are pre-formatted manual pages. The files whose names end in .1, .5, and .8 are unformatted. The method to format them for printing is described in ../READ_ME. [3]

[3] Note that the READ_ME here in the src directory is different from the one in the parent directory (../READ_ME), even though they both have the same name.

The files whose names end in .c and .h are the actual source. The makesendmail file is a shell script that makes building easy, and the READ_ME file contains the latest information about building. You should read the latter now. Pay special attention to the section titled OPERATING SYSTEM AND COMPILE QUIRKS. No matter what your operating system, this section probably contains information that is important to you.