DCE for the HP e3000 (B3821-90002)

Programming Notes
Building DCE Programs
Chapter 4
46
Building DCE Programs
Header Files
In addition to the standard POSIX libraries and HP C/XL functions, you may have to
include the DCE header files, which can be found in the /usr/include/dce directory. If your C
applications use Try/Catch for exception handling, you should include the following
statement in the C programs:
#include <dce/pthread_exc.h>
There are no MPE/iX equivalent libraries for /usr/lib/libbb.a or /usr/lib/libc_r.a. The reentrant
functions that are defined in MPE/iX and the thread-safe wrapper functions are in
/usr/lib/libdce.a.
MPE/iX does not have the file strings.h. The HP-UX strings.h includes string.h, sys/stdsyms.h and
some definitions that are strictly for C++ and HP-UX.
Compiler Flags
When compiling DCE applications using ANSI C under the MPE CI, set the following
compiler switches:
-D_POSIX_SOURCE -D_MPEXL_SOURCE -D_SOCKET_SOURCE -D_REENTRANT -Aa
When compiling under the MPE POSIX shell, you need the above flags except for the -Aa
option. If -Aa is set, /bin/c89 displays a large amount of error messages (by definition, the
POSIX environment always uses the ANSI C compiler).
Unresolved Externals
When porting applications from a UNIX environment to MPE/iX, you may receive
unresolved external errors during a compile, link, or run phase. It is likely that the
unresolved externals are not part of the POSIX.1 standard. To find out if a function is
defined in the POSIX environment, look at the manpage for that function on a UNIX
system. At the bottom of the manpage, there is a section titled STANDARD
CONFORMANCE, which lists the function name and the standard it conforms to. If the
manpage does not have POSIX.1 listed as one of the standards then that function is not
part of the MPE/iX POSIX Environment. To get around this porting issue, you may have
to write a routine to emulate the functionality for the unresolved external.