3.7. More Exercises

Exercise 3.1

You have got a set programs, each of which is created from its own assembly-language source file (suffix .asm). Each program can be assembled into two versions, one with error-checking code assembled in and one without. You could assemble them into files with different suffixes (.eobj and .obj, for instance), but your linker only understands files that end in .obj. To top it all off, the final executables must have the suffix .exe. How can you still use transformation rules to make your life easier (Hint: assume the errorchecking versions have ec tacked onto their prefix)?

Exercise 3.2

Assume, for a moment or two, you want to perform a sort of “indirection” by placing the name of a variable into another one, then you want to get the value of the first by expanding the second somehow. Unfortunately, PMake does not allow constructs like:


What do you do? Hint: no further variable expansion is performed after modifiers are applied, thus if you cause a $ to occur in the expansion, that is what will be in the result.

This, and other documents, can be downloaded from ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/.

For questions about FreeBSD, read the documentation before contacting <questions@FreeBSD.org>.
For questions about this documentation, e-mail <doc@FreeBSD.org>.