Problem with writing in a file using fprintf

This is a discussion on Problem with writing in a file using fprintf within the C Programming forums, part of the General Programming Boards category; Good morning! I have a problem using fprintf. I try to print a linked list which consists of nodes(structs). When ...

  1. #1
    g_p
    g_p is offline
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    Problem with writing in a file using fprintf

    Good morning!

    I have a problem using fprintf.
    I try to print a linked list which consists of nodes(structs).
    When i try to print the list to the standard output using printf evrything is ok
    e.g. i do :

    printf("%d, %d, %s, %s\n",p->l, p->t, p->a, p->b);

    //p is pointer to the struct

    Now i try to print the linked list in a file i do:
    Code:
    if( ( fp = fopen(argv[1],"w") ) == NULL )
                            printf("File couldn't be opened\n");
                    else {
                            p = head;
                            while( p != NULL) {
                                    fprintf(fp, "%d, %d,%s,%s\n",p->l, p->t, p->a, p->b);
                                    p = p->next;
                                            }
                            }
                     fclose(fp);


    But nothing is being typed to the file!
    What do i do wrong?

    Thanks in advance!

  2. #2
    Registered User ssharish2005's Avatar
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    Well nothing looks to me wrong over in the above code. Post use some more code.

    Need proper indendation
    Code:
    if( ( fp = fopen(argv[1],"w") ) == NULL )
        printf("File couldn't be opened\n");
    else 
    {
         p = head;
         while( p != NULL) 
         {
                fprintf(fp, "%d, %d, %s, %s\n",p->l, p->t, p->a, p->b);
                p = p->next;
         }
    }
    fclose(fp);
    ssharish2005

  3. #3
    g_p
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    Well the problem is with that fprintf,
    The other program is fine as i can see
    cause when i try to print the list using the printf
    the list is printed!

  4. #4
    Registered User ssharish2005's Avatar
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    well your fprintf statment is right, it follows the synatx and looks to me right

    ssharish2005

  5. #5
    g_p
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    Well, now it works!
    I don't know why it works now,I just changed the input file i was giving previously!
    Now everything seems fine for the time being!

    Thank you!

  6. #6
    Captain Crash brewbuck's Avatar
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    Quote Originally Posted by g_p View Post
    Well, now it works!
    I don't know why it works now,I just changed the input file i was giving previously!
    Now everything seems fine for the time being!

    Thank you!
    You shouldn't feel satisfied just because the problem inexplicably disappears. Go back to file that wasn't working and figure out why.

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