Compare part of an input string using strcmp() in C

c strcmp
user1872384 picture user1872384 · Dec 12, 2012 · Viewed 32.8k times · Source

Normally strcmp is used with two arguments [e.g. strcmp(str1,"garden")], and it will return 0 if both are the same.

Is it possible to compare part of the input, say the first five character of the input? (for example, strcmp(str1,"garde",5))

#include <stdio.h>
#include<string.h>

int main(void) {

    char str1[] = "garden";

    if (strcmp(str1, "garden") == 0)
    {
        printf("1");
    }
    if (strcmp(str1, "garden", 6) == 0)
    {
        printf("2");
    }
    if (strcmp(str1, "garde", 5) == 0)
    {
        printf("3");
    }
    return 0;
}

Answer

goji picture goji · Dec 12, 2012

Use strncmp:

if (strncmp(str, "test", 4) == 0) { printf("it matches!"); }

See http://www.cplusplus.com/reference/cstring/strncmp/ for more info.

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