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Reading file using fscanf() in C

I need to read and print data from a file.
I wrote the program like below,

#include<stdio.h>
#include<conio.h>
int main(void)
{
char item[9], status;

FILE *fp;

if( (fp = fopen("D:\\Sample\\database.txt", "r+")) == NULL)
{
    printf("No such file\n");
    exit(1);
}  

 if (fp == NULL)
{
    printf("Error Reading File\n");
}

while(fscanf(fp,"%s %c",item,&status) == 1)  
{  
       printf("\n%s \t %c", item,status);  
}  
if(feof(fp))  
{            
         puts("EOF");     
}  
else  
{  
 puts("CAN NOT READ");  
}  
getch();  
return 0;  
}  

the database.txt file contains
Test1 A
Test2 B
Test3 C

When I run the code, it prints

CAN NOT READ.

Please help me to find out the problem.

like image 804
Guru Avatar asked Jul 28 '10 10:07

Guru


2 Answers

First of all, you're testing fp twice. so printf("Error Reading File\n"); never gets executed.

Then, the output of fscanf should be equal to 2 since you're reading two values.

like image 161
Hamid Nazari Avatar answered Oct 12 '22 17:10

Hamid Nazari


scanf() and friends return the number of input items successfully matched. For your code, that would be two or less (in case of less matches than specified). In short, be a little more careful with the manual pages:

#include <stdio.h>
#include <errno.h>
#include <stdbool.h>

int main(void)
{
    char item[9], status;

    FILE *fp;

    if((fp = fopen("D:\\Sample\\database.txt", "r+")) == NULL) {
        printf("No such file\n");
        exit(1);
    }

    while (true) {
        int ret = fscanf(fp, "%s %c", item, &status);
        if(ret == 2)
            printf("\n%s \t %c", item, status);
        else if(errno != 0) {
            perror("scanf:");
            break;
        } else if(ret == EOF) {
            break;
        } else {
            printf("No match.\n");
        }
    }
    printf("\n");
    if(feof(fp)) {
        puts("EOF");
    }
    return 0;
}
like image 44
Michael Foukarakis Avatar answered Oct 12 '22 15:10

Michael Foukarakis