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How to catch an unintended interpolation function?

After reading my Expert C Programming book, I stumbled upon a chapter on the interpolation function and how this can lead to serious trouble finding errors if this happens unintentionally.

The example in the book is as follows:

my_source.c

mktemp() { ... }

main() {
  mktemp();
  getwd();
}

Libc

mktemp(){ ... }
getwd(){ ...; mktemp(); ... }

According to the book, what happens in main()is that mktemp()(the standard C library function) is placed by the implementation in my_source.c . Despite what main()causes my implementation of the mktemp()intended behavior, having getwd()(another C library function) also calls my implementation mktemp().

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An easy way to protect again is to try to make all external sysmbols in your application or library unique. For modules that you intend to use only on a limited basis, this is quite easy to do, making sure that all extenal characters in your module are unique by adding a unique identifier.

For modules that are widespread, introducing unique names, is a problem.

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