Portable C programs are clear, reliable, and easily
maintainable and can be easily transported from one machine to another.
With few modifications, C programs written with portability in mind
can be recompiled and run on different computers. For specific information
on system dependencies, refer to the HP C/HP-UX Reference
Manual.
The ANSI standard specifies which aspects of C are required
to work the same on conforming implementations, and which can work
differently. Since many ANSI-conforming compilers are available
on a wide variety of platforms, it is easy to develop portable programs.
HP C, when invoked in ANSI mode and used with the preprocessor (cpp),
headers, libraries, and linker, conforms fully with the standard.
This chapter discusses some guidelines for making your C programs
more portable. Emphasis is placed on HP C specific portability issues,
especially as they relate to porting from pre-ANSI mode HP C (Kernighan
and Ritchie plus BSD extensions) to ANSI mode HP C.
