strcmp will test two strings for equallity.
Returns : < 0 if s1 is less than s2 0 if s1 == s2 > 0 if s1 is greater than s2This function probably provides too much information by indicating which string is lexicographically greater. The net result means that the strcmp return code is logically incorrect because it returns a FALSE value when the strings match.
strstr Find a sub string in a string.
strchrLocate a character in a string.
index Locate a character in a string.
strcasecmp Compare strings, ignoring case.