"Unix: just enough potholes and bear traps to keep an entire valley going."
If you don't understand how to use sharp tools, you may hurt yourself and others. Documentation for fork() clearly explains why and when fork() returns -1. Those that find the man page lacking or elusive may get more out of an earnest study of W. Richard Stevens' book, Advanced Programming in the UNIX Environment. In any case, every system programmer should own a copy and understand its contents.
If you don't understand how to use sharp tools, you may hurt yourself and others. Documentation for fork() clearly explains why and when fork() returns -1. Those that find the man page lacking or elusive may get more out of an earnest study of W. Richard Stevens' book, Advanced Programming in the UNIX Environment. In any case, every system programmer should own a copy and understand its contents.