Header File 

stdlib.h, math.h 

Category 

Math Routines, Inline Routines 

Prototype 

int abs(int x); 

Description 

Returns the absolute value of an integer. 

abs returns the absolute value of the integer argument x. If abs is called when stdlib.h has been included, it's treated as a macro that expands to inline code. 

If you want to use the abs function instead of the macro, include 

#undef abs  

in your program, after the #include <stdlib.h>. 

Return Value 

The abs function returns an integer in the range of 0 to INT_MAX, with the exception that an argument with the value INT_MIN is returned as INT_MIN. The values for INT_MAX and INT_MIN are defined in header file limit.h. 

Example  

#include <stdio.h>
#include <math.h>
int main(void)
{
  int number = -1234;
  printf("number: %d  absolute value: %d\n", number, abs(number));
  return 0;
}

Portability