GCC for beginners

This page is intended to be a collection of tips for those who are new to GCC on RISC OS, perhaps those who are used to Acorn C/C++. For a tutorial, see also the GCC tutorial.

= Makefiles = See this question in the RISC OS C Programming FAQ.

= Header file naming = On Unix, there's a given hierarchy of header files. So when you install the C library header files (equivalent to UnixLib) they go in /usr/include. So you get files like: /usr/include/stdio.h /usr/include/string.h /usr/include/setjmp.h /usr/include/time.h /usr/include/sys/time.h /usr/include/sys/quota.h /usr/include/net/ethernet.h

When you install other packages they slot into this structure. For example the GPIB driver library I've been using today lives in: /usr/include/gpib/ib.h and if you install the Linux kernel headers you get things like: /usr/include/linux/adfs_fs.h (the ADFS driver for Linux) /usr/include/linux/joystick.h and so on.

The name inside the pointy brackets <> is effectively the path without /usr/include on the front. So refers to /usr/include/sys/types.h while refers to /usr/include/bits/types.h
 * 1) include 
 * 1) include 

They're different files, and they have different pathnames (in fact, in glibc on Linux, sys/types.h has a #include ). In the list above notice there are two time.h files - you'd refer to the first one as plain  and the second as 

Of course it's slightly more complicated than that - /usr/include is a system-wide path so you need to be the machine administrator to add things to it. If I'm not administrator I might put some header files in some other directory (/home/theo/myincludes say) and use a -isystem to refer to them.