Re: problem

From: Pascal Bourguignon (spam_at_mouse-potato.com)
Date: 09/27/05

  • Next message: Wayne C. Morris: "Re: problem" 
    Date: Tue, 27 Sep 2005 18:03:29 +0200

    hirenshah.05@gmail.com writes:

    > I am trying to a program which takes the data from user and write in
    > file. I have written the code below. but when i am displaying data from
    > file; only first data is correct; others are random. i think there is
    > problem while writing in file.
    >
    >
    >
    > struct st
    > {
    > char ch[60];
    > int n;
    > };
    >
    > int main()
    > {
    > st s;
    > printf("enter");
    > scanf("%s",s.ch);

    If the user types:

    I-am-trying-to-do-a-program-which-takes-the-data-from-user-and-write-in-a-file.

    then your program will crash because scanf will overwrite s.n and the
    stack with the characters beyond the 60th.

    NEVER use scanf "%s" !

    It'd use fgets, or scanf("%59s",...);

    > printf("enter no.");
    > scanf("%d",&s.n);
    > adddata(&s);

    You've declared that main returns an integer so return it!
       return(0);

    > }
    >
    >
    >
    > add data(st *x)

    what is the add type?
    Why do you send us programs that don't even compile successfully?

    > {
    > int fd;
    > fd=open("records",O_CREAT|O_RDWR,0644);
    > close(fd);

    And what would happen if some other process executed: rm records
    right now? This open/close is useless!

    > fd=open(path,O_CREAT|O_APPEND|O_RDWR);

    What is path?
    Why do you send us programs that don't even compile successfully?

    > fdw=write(fd,x,sizeof(s));

    What is s? What is fdw?
    Why do you send us programs that don't even compile successfully?

    > close(fd);
    > }

    Where is defined adddata?
    Why do you send us programs that don't even compile successfully?

    > Then i have created another function to read from file "records" and
    > display all data entered.
    >
    > But when i am adding data , Only first data enter is correct ; rest of
    > the data are random. I am not getting where is problem. 

    -- 
__Pascal Bourguignon__                     http://www.informatimago.com/
Litter box not here.
You must have moved it again.
I'll poop in the sink.
  • Next message: Wayne C. Morris: "Re: problem"