How to change function name in a library

I have two separate library files with a function of same Name and Passing parameter. How can I use these two library files in a single project? Or how to change the function name in one library? ...
How to change function name in a library

I have two separate library files with a function of same Name and Passing parameter. How can I use these two library files in a single project? Or how to change the function name in one library? ...
..\display.h(72): warning: #231-D: declaration is not visible outside of function

..\display.h(72): warning: #231-D: declaration is not visible outside of function I got message when I included a header file containing this line: void DISPLAY_string_date_time(const struct...
..\display.h(72): warning: #231-D: declaration is not visible outside of function

..\display.h(72): warning: #231-D: declaration is not visible outside of function I got message when I included a header file containing this line: void DISPLAY_string_date_time(const struct...
Two different functions but with the same name in separate libraries

I have two libraries, named a.lib and b.lib. Both libraries have a function char test(void), but return different characters. a.c (a.lib) char test(void); char test(void) { return 'a'; } b.c (b...