Next:

5.5 Library Functions ===================== The following macros check for particular C library functions. If there is no macro specifically defined to check for a function you need, and you don't need to check for any special properties of it, then you can use one of the general function-check macros.

- Function Portability
- Pitfalls with usual functions
- Particular Functions
- Special handling to find certain functions
- Generic Functions
- How to find other functions