lvalue problem

[sebajun]

Hi guys, I'm getting the error:

30:80: error: lvalue required as left operand of assignment

I'm not sure why this is happening as surely my char pointers can be changed.

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

int main(int argc, char *argv[]){
    
    FILE *fp1;
    FILE *fp2;
    FILE *fp3;
    
    char *p1;
    char *p2;
    char *p3;

    int temp1;
    int temp2;
    int temp3;
    int counter = 0;

    char string1[100];
    char string2[100];
    char string3[100];    

    fp1 = fopen(argv[1], "r");
    fp2 = fopen(argv[2], "r");
    fp3 = fopen(argv[3], "r");


    while(p1 = fgets(string1, 100, fp1) && p2 = fgets(string2, 100, fp2) && p3 = fgets(string3, 100, fp3)){
	if(p1 == NULL || p2 == NULL || p3 == NULL){
	    counter++;
        }
	if(counter>2){
	    break;
        }
        sscanf(string1, "%d", &temp1);
	sscanf(string2, "%d", &temp2);
        sscanf(string3, "%d", &temp3);
        printf("%d\n%d\n%d\n", temp1, temp2, temp3);
    } 	
    
    fclose(fp1);
    fclose(fp2);
    fclose(fp3);		

    return 0;
    
}


     

[cppbegin]

IMHO you are assigning 3 times in line 30 where comparing is expected.
Maybe you could explain, what you are trying to do from line 30 to 41.