Format
#include <string.h>
int strncmp(const char *string1, const char *string2, size_t count);Language Level: ANSI
Threadsafe: Yes.
Description
The strncmp() function compares string1 and string2 to the maximum of count.
Return Value
The strncmp() function returns a value indicating the relationship between the strings, as follows:
| Value | Meaning |
| Less than 0 | string1 less than string2 |
| 0 | string1 equivalent to string2 |
| Greater than 0 | string1 greater than string2 |
Example that uses strncmp()
This example demonstrates the difference between the strcmp() function and the strncmp() function.
#include <stdio.h>
#include <string.h>
#define SIZE 10
int main(void)
{
int result;
int index = 3;
char buffer1[SIZE] = "abcdefg";
char buffer2[SIZE] = "abcfg";
void print_result( int, char *, char * );
result = strcmp( buffer1, buffer2 );
printf( "Comparison of each character\n" );
printf( " strcmp: " );
print_result( result, buffer1, buffer2 );
result = strncmp( buffer1, buffer2, index);
printf( "\nComparison of only the first %i characters\n", index );
printf( " strncmp: " );
print_result( result, buffer1, buffer2 );
}
void print_result( int res, char * p_buffer1, char * p_buffer2 )
{
if ( res == 0 )
printf( "\"%s\" is identical to \"%s\"\n", p_buffer1, p_buffer2);
else if ( res < 0 )
printf( "\"%s\" is less than \"%s\"\n", p_buffer1, p_buffer2 );
else
printf( "\"%s\" is greater than \"%s\"\n", p_buffer1, p_buffer2 );
}
/***************** Output should be similar to: *****************
Comparison of each character
strcmp: "abcdefg" is less than "abcfg"
Comparison of only the first 3 characters
strncmp: "abcdefg" is identical to "abcfg"
*/Related Information