Help on simple file functions

This is a discussion on Help on simple file functions within the C Programming forums, part of the General Programming Boards category; fgets(&s, sizeof(contact_rec), stdin); it is bad s is 1 byte you give pointer to it and tell fgets that you ...

  1. #16
    CSharpener vart's Avatar
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    fgets(&s, sizeof(contact_rec), stdin);
    it is bad
    s is 1 byte
    you give pointer to it and tell fgets that you have place for sizeof(contact_rec) bytes... Not good... Not good at all... Neveer lie about memory size you own.
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  2. #17
    ATH0 quzah's Avatar
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    Quote Originally Posted by enjoyincubus
    @quzah

    ive read what youve wrote

    if you mean the data that are being ask by the user , i already have them

    it works w/ view function
    Yeah, so? You're not even remotely paying attention to what your code does.
    Quote Originally Posted by enjoyincubus
    it will result into an "Error: Record not found"

    here is my code again:
    Of course it does. It'd be ........ing miracle if it actually worked. I don't even want to attempt to calculate the odds on that working right. I'll comment your code, since you apparently have no idea what you're doing.
    Code:
    void search (void) /* first, you're not passing any arguments... */
    {
    
    FILE *fp; 
    contact_rec X[4]; /* declare a local array, which holds nothing right now... */
    char s;
    int i = 0;
    
    if ((fp = fopen ("phone.dat", "rb")) == NULL) /* open the file for reading... */
    	{
    		printf ("Error : file is does not exist");
    		exit(1);
    	}
    
        	printf ("Enter a name to be search: ");
        	fgets(&s, sizeof(contact_rec), stdin); /* get something to search for... */
    
    	for ( i = 0; i < 5; i++)
    	{
    		 /* look through the array, which contains nothing useful... */
    		if ((strcmp (&s, X[i].name)) == 0)
    		{
    
    			printf("%s", X[i].tel);
    			printf("%s", X[i].cel);
    
    		}
    
    		else
    		{
    			 /* somehow be mystified as to why it doesn't work... */
    			printf("Error : Record not found");
    
    			fclose(fp);
    		}
          	 }
    /* return without closing the file, since you only close it on error... */
    }
    Like I said, you never actually read. Well that's actually really really apparent. You never actually read what I write, and you never actually read anything from your file here, just like I keep saying!


    Quzah.
    Hope is the first step on the road to disappointment.

  3. #18
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    umm ok, so how do i do that?

  4. #19
    Registered User whiteflags's Avatar
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    A good lesson ought to help. http://c-faq.com/~scs/cclass/int/sx3.html

    You're looking for information concerning reading binary files, but I would read the whole lesson at some point. Now's good.

  5. #20
    ATH0 quzah's Avatar
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    Quote Originally Posted by enjoyincubus
    umm ok, so how do i do that?
    What do you mean "how do I do that"? Did you write any of this code, or did you just steal it from someone else who doesn't have a clue?

    You do it the same way you did it in your view function. You really should be thinking this through better. Make a function to read the info into memory. Make your other functions take that information as an argument to the function, so you can edit it, view it, search it, etc.


    Quzah.
    Hope is the first step on the road to disappointment.

  6. #21
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    I made this code


    ill try to do what you just said

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