C program, header file not found

I am using 2.6.18 CentOS. I am using headers, which on compiling is saying not found. Any idea, as how to resolve it?

timer_开发者_高级运维ex1.c:3:24: error: sys/netmgr.h: No such file or directory
timer_ex1.c:4:26: error: sys/neutrino.h: No such file or directory
timer_ex1.c:5:25: error: sys/siginfo.h: No such file or directory

---

Obviously, the files aren't found in the include path.

To get rid of that, locate sys/netmgr.h on your system. The parent path of sys must be in the include paths passed to the compiler when building timer_ex1.c