Programming Perl, 4th Edition

Non-Perl Manpages

When we refer to non-Perl documentation, as in getitimer(2), this refers to the getitimer manpage from section 2 of the Unix Programmer’s Manual.^[3] Manpages for syscalls such as getitimer may not be available on non-Unix systems, but that’s probably okay, because you couldn’t use the Unix syscall there anyway. If you really do need the documentation for a Unix command, syscall, or library function, many organizations have put their manpages on the Web—a quick search of Google for crypt(3) manual will find many copies.

Although the top-level Perl manpages are typically installed in section 1 of the standard man directories, we will omit appending a (1) to those manpage names in this book. You can recognize them anyway because they are all of the form “perlmumble”.

^[3] Section 2 is only supposed to contain direct calls into the operating system. (These are often called “system calls”, but we’ll consistently call them syscalls in this book to avoid confusion with the system function, which has nothing to do with syscalls). However, systems vary somewhat in which calls are implemented as syscalls, and which are implemented as C library calls, so you could conceivably find getitimer(2) in section 3 instead.