Segmentation Error in Code...

[sanjeebkdeka]

I am getting "Segmentation Fault" for the following program. How to avoid it.

#include<stdio.h>
#include<stdlib.h>
#pragma align
void print(char*,int);

struct data{
int a;
char b;
}

main()
{
int n;
char *ptr;
struct data *p;
p->a=7;
p->b="c";

printf("Enter n:");
scanf("%d",&n);
print(ptr,n);
}

print(char *ptr1,int m)
{
struct data *ptr2;
int i;
ptr2=(struct data*)ptr1;
for(i=0;i<m;i++)
printf("a=%d\tb=%c",ptr2->a,ptr2->b);

}

[Savage]

I am getting "Segmentation Fault" for the following program. How to avoid it.

#include<stdio.h>
#include<stdlib.h>
#pragma align
void print(char*,int);
 
struct data{
            int a;
            char b;
           }
 
main()
{
 int n;
 char *ptr;
 struct data *p;
 p->a=7;
 p->b="c";
 
 printf("Enter n:");
 scanf("%d",&n);
 print(ptr,n);
}
 
print(char *ptr1,int m)
{
 struct data *ptr2;
 int i;
 ptr2=(struct data*)ptr1;
 for(i=0;i<m;i++)
     printf("a=%d\tb=%c",ptr2->a,ptr2->b);

}

You need to allocate memory for struct pointer.

Are u using C or C++?

Savage

[Silent1Mezzo]

I am getting "Segmentation Fault" for the following program. How to avoid it.

 
#include<stdio.h>
#include<stdlib.h>
#pragma align
void print(char*,int);
 
struct data{
            int a;
            char b;
           }
 
main()
{
 int n;
 char *ptr;
 struct data *p;
 p->a=7;
 p->b="c";
 
 printf("Enter n:");
 scanf("%d",&n);
 print(ptr,n);
}
 
print(char *ptr1,int m)
{
 struct data *ptr2;
 int i;
 ptr2=(struct data*)ptr1;
 for(i=0;i<m;i++)
     printf("a=%d\tb=%c",ptr2->a,ptr2->b);
 
}

Looks like a C program to me
You'll have to allocate memor for each of the data pointers.
p = malloc(size you need);

[Savage]

Looks like a C program to me
You'll have to allocate memor for each of the data pointers.
p = malloc(size you need);

Yes it does looks like a C program,but u can never know,maybe OP is using printf and scanf in c++.

Savage

[sanjeebkdeka]

Yes it does looks like a C program,but u can never know,maybe OP is using printf and scanf in c++.

Savage

Hi,

Could you please write the complete C code? I am an infant in C programming. I tried allocating memory for the structure pointers, i declared. But still it is showing segmentation fault.
Please help.

[gpraghuram]

Hi,
Allocate memory like this
struct data *p=(struct data*)malloc(sizeof(struct data));
and init the char value with single quotes
p->b='c';

Then in print you are simply typecasting and printing the structure, but the char*ptr is not initialized properly due to which also it may crash

Check it

Raghu

[kky2k]

exactly what you want to do it in your "print" function..if you come up with that answer probably everyone will help u out