Unable to open a file for reading

Hi
I am a beginer to C Programming.I was trying to open a .txt file for reading but couldnt do that this is my code..Help me out.

Code:

---

#include<stdio.h>
#include<conio.h>
main()
{
FILE *fp;
clrscr();
fp=fopen("raghu.txt","r");
if(fp==NULL)
printf("ERROR IN OPENING THE FILE");
else
{
printf("hi");
fprintf(fp,"\n HI");
}
fgetc(fp);
fclose(fp);
getch();
}

---

1. You didn't ask a question.
2. You're checking if fp is NULL, but if it is, you use it anyway.
3. You are trying to write and read on a file you're opening for reading.
4. You're using non-standard code.

So your question is?

I did not get the 4 point.."You're using non-standard code." can you tell me more about that ,Mac

you should write
int main()
explicitely

and not ignore the return value of fgetc

Quote:

---

Originally Posted by raghuveerd

I did not get the 4 point.."You're using non-standard code." can you tell me more about that ,Mac

---

conio.h is not a standard header
all function declared in it - are not standard

using them - makes code not portable - You cannot compile your code on differrent compiler / OS.


You should avoid posting such code - it makes hard to compile it by the people you ask for help... Not many people will take your code, remove non-portable parts just to compile and see what is the problem...

You can avoid such code in your application at all (better) or just remove it before posting a sniplet of the code to the board

i made some changes ..but still cant read anything

Code:

---

#include<stdio.h>
#include<conio.h>
int main()
{
FILE *fp;
clrscr();
fp=fopen("raghu.txt","r");
if(fp==NULL)
printf("ERROR IN OPENING THE FILE");
else
{
printf("hi");
fprintf(fp,"\n HI");
}

fclose(fp);
getch();
}

---

you still opening for reading - and trying to write
don't close file if you failed to open it - close only if openign was successful
indent your code properly

I am sorry but i have a questions..Is this forum not intended for beginers in C Programming. I want to know if i am really posting silly questions wasting time of experienced programmers.

Quote:

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Originally Posted by raghuveerd

I am sorry but i have a questions..Is this forum not intended for beginers in C Programming. I want to know if i am really posting silly questions wasting time of experienced programmers.

---

Of course it's a place for new C programmers to ask questions.

The problem, however, is that you didn't ask a question. You dumped code here with a blanket "doesn't work" message. Of course it doesn't work. If it worked, you wouldn't be asking for help. It's irritating to try to help solve a problem with no information on said problem.

As far as your code goes, you're still opening a file for reading, but you're trying to write to it. You've been alerted about this like twice before. This will not work, and could result in very weird behavior.

> fp=fopen("raghu.txt","r");
This is for reading from a file.

> fprintf(fp,"\n HI");
This is for writing to a file.

Basically, decide what you want to do, then edit the code accordingly.

For example, fgets() and fscanf() are file reading functions.

The thing i want to do is to print the text in raghu.txt on the screen. Can i do that!

Yes, you can. Use fgets().

read it in with the functions Salem wrote, then printf it out.

Thanks a lot..i got it now..actually i was confused with the what fprintf and fscanf does...
thanka a lot Mac,Salem,Rob,vart

Now i can print the text in my file on to the screen..is the right way to do it

Code:

---

#include<stdio.h>

int main()
{
FILE *fp;
char *str;
clrscr();
fp=fopen("raghu.txt","r");
if(fp==NULL)
    printf("ERROR IN OPENING THE FILE");
else
    {
    printf("hi,this is the text in your file\n");
    fgets(str,20,fp);
    }
printf("&#37;s",str);
fclose(fp);

getch();
}

---

Since it doesn't compile, I would say no. ;)

Also, str needs to be an array. You can't read 20 chars into a buffer of size 0. BTW, if the file doesn't exist, why try to print the array?

printf("%s",str); should be inside the braces. same with fclose. Follow the program flow for if the file fails to open. str will be uninitialized.