Loop Through TXT File ...

try this

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

int main()
{
      FILE *fp;
      char str[255];
      
      // if file opening in binary mode fails
      if ( (fp = fopen("myfile.txt", "r")) == NULL )
      {
            printf("Error opening file");

            // 1: EXIT_FAILURE
            return 1;
      }
      // opening file is successful
      else
      {
            while ( !feof(fp) )
            {
                  fscanf(fp, "%s", str);
                  printf("%s read and its length is %d\n", str, strlen(str));
            }

            fclose(fp);

            return 0;
      }
}


hongjun

Great code, One thing though:

myfile.txt:
jay.com
apple.com
blah.com

./loop
jay.com read and its length is 7
apple.com read and its length is 9
blah.com read and its length is 8
blah.com read and its length is 8

Why does blah.com show up twice?

Thanks,

Jay

Infinity:

Although a stupid question, can I use C++ code in C?

Thanks,

Jay

>> Although a stupid question, can I use C++ code in C?

No. You can use C code in C++ though ... You can see C++ as a superset of C, but not the other way around.

Oh, I see why you asked. The site is called www.cplusplus.com because it is a reference for both C and C++. The links I gave though were for the C part.

I don't have this problem.
I am using Windows and I believe you are using Linux.
I cannot test it for you :(

As for your question on C++ on C, it should throw you errors or warnings if you are using gcc and your file extension is .c

hongjun

Thanks :D

Jay

>> Why does blah.com show up twice?

Because you didn't check the return value of fscanf :

                  if (fscanf(fp, "%s", str) == 1) {
                      printf("%s read and its length is %d\n", str, strlen(str));
                  }

reference page :

    http://www.cplusplus.com/reference/clibrary/cstdio/fscanf.html

Your file had a newline at the end of the last line, so the EOF was only set by the fscanf of the 4th iteration. That's why the last line appeared twice.

>> I don't have this problem.

The reason you didn't have this problem is not because you use Linux, but because you didn't have a newline after blah.com

                 if ( fscanf(fp, "%s", str) != -1 )

That's not sufficient. What if the return value is 0 ?

See the check I posted in my previous post ...

Yap.. Infinity is correct.
I realized it is because of the newline and so I just include the check.

Only after i posted, I then realized a return of 0 is also possible. So, for a more complete, check for == 1.
It has been ages since I last code a C program!

I actually went to search the net to code the above. haha!!! C used to be my best language during my diploma days. I am getting old.

hongjun