Microchip Technology SW006023-2N Data Sheet
MPLAB
®
XC32 C/C++ COMPILER
USER’S GUIDE
2012 Microchip Technology Inc.
DS51686E-page 159
Chapter 13. Library Routines
13.1
USING LIBRARY ROUTINES
Library functions or routines (and any associated variables) will be automatically linked
into a program once they have been referenced in your source code. The use of a func-
tion from one library file will not include any other functions from that library. Only used
library functions will be linked into the program output and consume memory.
into a program once they have been referenced in your source code. The use of a func-
tion from one library file will not include any other functions from that library. Only used
library functions will be linked into the program output and consume memory.
Your program will require declarations for any functions or symbols used from libraries.
These are contained in the standard C header (.h) files. Header files are not library
files and the two files types should not be confused. Library files contain precompiled
code, typically functions and variable definitions; the header files provide declarations
(as opposed to definitions) for functions, variables and types in the library files, as well
as other preprocessor macros.
These are contained in the standard C header (.h) files. Header files are not library
files and the two files types should not be confused. Library files contain precompiled
code, typically functions and variable definitions; the header files provide declarations
(as opposed to definitions) for functions, variables and types in the library files, as well
as other preprocessor macros.
#include <math.h> // declare function prototype for sqrt
int main(void)
{
double i;
// sqrt referenced; sqrt will be linked in from library file
i = sqrt(23.5);
}