Segmentation error in cprogram

[Satya.tenneti]

HI All

I am new to c programming on linux. I've tried a simple program on file. It works fine in windows environment (Turbo c). But whenever I try to run it in linux I am getting error "Segmentation Fault".

#include<stdio.h>
#include<stdlib.h>
struct std
{
char sname[10];
int rno;
char class[10];
};
struct emp
{
char ename[10];
int eid;
char desg[10];
};

int main()
{
FILE *fp,*fs;
char ch=' ';
struct std s;
struct emp e;
fp=fopen("stdu","wb");
if(fp==NULL)
{
printf("\n can not open file");
exit(0);
}
do
{
printf("\n enter student details:");
printf("\n enter student name, number and class");
scanf("%s %d %s",s.sname,&s.rno,s.class);
fwrite(&s,sizeof(s),1,fp);
printf("\n do you want to continue(y/n)");
fflush(stdin);
scanf("%c",&ch);
printf("u r in the student details\n");
}while(ch == 'y');

fclose(fp);
fs=fopen("employee","wb");
if(fs==NULL){
printf("\n CAN NOT OPEN FILE");
exit(0);
}
do
{
printf("\n enter employee details");
printf("\n enter ename,eid and designation");
scanf("%s %d %s",e.ename,&e.eid,e.desg);
fwrite(&e,sizeof(e),1,fs);
printf("\n Do you want to continue(y/n)");
fflush(stdin);
scanf("%c",&ch);
}while(ch=='y');

fclose(fs);

return 0;
}


Pl help me If I went wrong in my code.


Thanks in advance
Satya

[rrojas1979]

You need to say what you were doing when you got the segmentation fault, but without knowing anything else about how you're running the program, I can see an issue with your structure arrays:

struct std
{
     char sname[10];
     int rno;
     char class[10];
};

struct emp
{
     char ename[10];
     int eid;
     char desg[10];
};

sname, class, ename, and desg are limited to 9 characters. If you entered strings longer than 9 characters, you would probably get a segmentation fault since your character arrays would be too small and you would overwrite them.

You should add a length check on your input, or alternatively increase the size of those arrays to something like 1024 chars...

[wowbag1]

Hi,
I agree with rrojas1979 about the size of arrays, also I have copied your code & compiled it run it and cannot get a segmentation fault yet.
Although it does behave oddly depending on what you input.

wowbag1

[Satya.tenneti]

I am able to read the student details successfully, but when I try to read the employee details I am gettin segmentation fault error

I am trying with strings lower than 9 characters anyhow...

I have changed the string size to 1024 but still the problem arising...

any help..


Thanks-Satya

[wje_lf]

What does gdb say about where your program gets the SIGSEGV?

[gemlin]

Hi,
How you are compiling your program is importent thing here...post that o/p to here..will guess error easily...
otherwise use GDB..
rgds,
gemlin