guys, recently I want to learn to develop some system-oriented programs in C on Android. For example, git code link
like this, at least you have to understand it first and can change it slightly.
now I want to find some systematic books or videos to learn, but I don"t know which category this belongs to. I looked at the catalogue of some books in linux c and found it was not very relevant. For example,

-sharpinclude <stdlib.h>
-sharpinclude <stdbool.h>
-sharpinclude <string.h>
-sharpinclude <dirent.h>
-sharpinclude <signal.h>
-sharpinclude <sys/mman.h>
// -sharpinclude <asm/ptrace.h>
-sharpinclude <sys/wait.h>
-sharpinclude <sys/ptrace.h>

things in this pile of, sys asm directories

there is also the data structure of pid_t, and the device-related data type of uint32_t (seemingly)

there are also a bunch of methods for system calls.

this bunch of macros

-sharpif defined(__i386__)  
-sharpdefine pt_regs         user_regs_struct  
-sharpendif 

I hope my brothers can give me a more systematic list of books, or keywords.