Write a c language program as required

Write the function int convertString(char *inString, char **outString) If either inString or outString is NULL, then this function should return 1. Otherwise, the function will take an input string, allocate a new string of the same length, call tolower () on each character in the input string, and put the result in the corresponding place in the output string. It will pass the new string through outString, as a pass-by-reference parameter, and will return the number of characters in the input string