strcmpi() Function in C: Case-Insensitive String Comparison

strcmpi() function in C is same as strcmp() function. But, strcmpi( ) function is not case sensitive. i.e, "S" and "s" are treated as same characters. Where as, strcmp() function treats "S" and "s" as different characters.

Syntax

int strcmpi ( const char * strng1, const char * strng2 );

Parameters

strng1 -first string
strng2 -Second string

Returns

Return Value	Description
Less than zero	strng1 is less than strng2 (strng1 < strng2)
Greater than zero	strng1 is greater than strng2 (string1 > string2)
Zero	strng1 is equal to strng2

Program

#include <stdio.h>
#include <string.h>
int main( )
{
   char strng1[ ] = "atnyla" ;
   char strng2[ ] = "atatnyla" ;
   int i, j, k ;
   i = strcmpi ( strng1, "ATNYLA" ) ;
   j = strcmpi ( strng1, strng2 ) ;
   k = strcmpi ( strng1, "f" ) ;
   printf ( "\n%d %d %d \n", i, j, k ) ;
   return 0;
}

Output

0 1 -1
Press any key to continue . . .

Points to be noted

1. strcmpi() function is non standard function which may not available in standard library in C.
2. Both functions compare two given strings and returns zero if they are same.