'defines.h' file not found

i have a question, i just moved to AT&T syntax and linux assembly programming. getting up-to-date with the new syntax and kernel syscalls was easy

now i found on a few tutorials, meant to make your way easier on the transition from intel and win assembly to AT&T and *nix assembly, reffrences to a defines.h file that had the most numbers for output souces and such already defined and passed along to a more human kind of abordation (i.e. $1 gets to be #STDOUT).

my question is if there are this sort of headers standardized and commonly used in the *nix asm world, or every coder makes his own.

searching google i found thousands of program samples that included the file but no reffrence was made to it, as though it was a naturaly found header file on every comp.

any comments on this will be very well apreciated...thanks!