index
Finds the first occurrence of a substring within a string.
int index(const char * str, const char * substr [, int start])
The index
function finds the position of the first occurrence of a
substring, substr, in a string, str, starting at an
optional position, start. If the specified value of the start position is
less than 0, it's implicitly set to 0. If the string is empty, index
returns 0. If no match is found for the substring within the string, index
returns -1.
Example 7-20 How to use index to identify the first occurrence of a substring within a string
BEGIN {
x = "#canyoufindapenguininthisstring?";
y = "penguin";
printf("The penguin appears at character %3d\n", index(x, y));
exit(0)
}