sendmail, 4th Edition

HAS...

Has specific system-call support Port, edit sendmail/conf.h

Macros that begin with HAS tell sendmail whether your system supports (has) certain system-library routines or variables. In general, you should need to define or undefine the compile-time macros shown in Table 3-3 only if you are porting sendmail to a new system. In that instance, you should also read sendmail/README for the latest information and pitfalls.

Each of these is turned on or off with an assignment of 1 or 0:

APPENDDEF(`confENVDEF', `-DHASSETSID=1')      ← turn on
APPENDDEF(`confENVDEF', `-DHASSETSID=0')      ← turn off

“Turning on” tells sendmail that your site has support for this system call (setsid(2) in this instance). “Turning off” tells sendmail to work around the lack of that support. When porting to a new system, you can test with one of the preceding confENVDEF statements and, if successful, put a permanent porting entry into sendmail/conf.h.

Table 3-3. HAS... compile-time macros for specific system-call support

Compile-time macro	System call
HASCLOSEFROM	closefrom(3)
HASFCHMOD	fchmod(2)
HASFCHOWN	fchown(2)
HASFDWALK	fdwalk(3)
HASFLOCK	flock(2)
HASGETDTABLESIZE	getdtablesize(2)
HASGETUSERSHELL	getusershell(3)
HASINITGROUPS	initgroups(3)
HASLSTAT	lstat(2)
HASNICE	nice(2)
HASRANDOM	random(3)
HASRRESVPORT	rresvport(3)
HASSETREUID	setreuid(2)
HASSETREGID	setregid(2)
HASSETRESGID	setresgid(2)
HASSETREUID	setreuid(2)
HASSETRLIMIT	setrlimit(2)
HASSETSID	setsid(2)
HASSETUSERCONTEXT ...