#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int random_no(int);
void calc_file_row_col(FILE *,int *,int *);
int main()
{
int i,j,z;
int temp=0;
int row,column;
FILE *fp;
char x,**a;
for(z=0;z<2;++z){
fp=fopen("poly.dat","r");
calc_file_row_col(fp,&row,&column); //Function which calculates
// the no of rows and column of a file
a=calloc(row,sizeof(char *)); // Declare a 2D array of size
// row by column
for(i=0;i<row;i++)
a[i]=calloc(column,sizeof(char));
for(i=0;i<row;i++) // Read the elements of file fp into
{ // array a
for(j=0;j<column+1;j++)
{
x=getc(fp);
if(x=='\n')
{}
else
{
*(*(a+i)+j)=x;
}
}}
fclose(fp);
fseek(fp,0,SEEK_SET);
temp=random_no(row); // Generates a random no. between 0 and row
printf("temp=%d\n",temp);
fp=fopen("poly.dat","w");
for(i=0;i<temp;i++) //Write elements from 0 to temp and then temp to row in file fp;
{
for(j=0;j<column;j++)
fprintf(fp,"%c",a[i][j]);
fprintf(fp,"\n");
}
for(i=temp+1;i<row;i++)
{
for(j=0;j<column;j++)
fprintf(fp,"%c",a[i][j]);
fprintf(fp,"\n");
}
fclose(fp);
for(i=0;i<row;i++)
free(a[i]);
free(a);
a=NULL;
}
return 0;
}
int random_no(int range)
{
int LOW=0;
int r;
time_t seconds;
time(&seconds);
srand((unsigned int)seconds);
r = rand() % (range - LOW + 1) + LOW;
return r%range;
}
void calc_file_row_col(FILE *poly,int *row,int *column)
{
int m=0;
int n=0;
char x;
fseek(poly,0,SEEK_SET);
while((x=getc(poly))!=EOF)
{
if(x=='\n'){
m++;
n=0;
}
else{
n++;
*column=n;
}
}
*row=m;
printf("row=%d column=%d\n",*row,*column);
fseek(poly,0,SEEK_SET);
}
when i try to use the class i wrote, i either get this:
*** glibc detected *** double free or corruption: 0x40236ff4 ***
and the proccess exits with an error code of 0;
or it segfaults. could someone look at my header file (with imp.) to give me some insight as to why its not working?
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