README (1386B)
1 2 This directory is intended for project header files. 3 4 A header file is a file containing C declarations and macro definitions 5 to be shared between several project source files. You request the use of a 6 header file in your project source file (C, C++, etc) located in `src` folder 7 by including it, with the C preprocessing directive `#include'. 8 9 ```src/main.c 10 11 #include "header.h" 12 13 int main (void) 14 { 15 ... 16 } 17 ``` 18 19 Including a header file produces the same results as copying the header file 20 into each source file that needs it. Such copying would be time-consuming 21 and error-prone. With a header file, the related declarations appear 22 in only one place. If they need to be changed, they can be changed in one 23 place, and programs that include the header file will automatically use the 24 new version when next recompiled. The header file eliminates the labor of 25 finding and changing all the copies as well as the risk that a failure to 26 find one copy will result in inconsistencies within a program. 27 28 In C, the usual convention is to give header files names that end with `.h'. 29 It is most portable to use only letters, digits, dashes, and underscores in 30 header file names, and at most one dot. 31 32 Read more about using header files in official GCC documentation: 33 34 * Include Syntax 35 * Include Operation 36 * Once-Only Headers 37 * Computed Includes 38 39 https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html