Programming

Hey guys I am reading a file in c that has a record like this:

1002:credit card:c:500.000000
2002:cred:d:200.000000

I am trying to read the file like this but I am getting a segmentation fault. Any ideas why?

Code:

while (fscanf(fp1, "%d:%[^:]:%c:%lf\n",&accountnumb[i],mainname[i],&type,&transactionc[i]) != EOF)
  {
  
  if(type=='d')
  {
  transactiond[i]=transactionc[i];
  }
  
      else
    {
    transactionc[i]=transactionc[i];
    }

Could we have a larger snippet of code that includes the definitions of your variables please.

Here are the variable definitions.

Code:

int i=0,k=0,counter=0,l=0,account,j=0;
char type,choice,name[NUMBS+1][NUMBS+1],mainname[NUMBS+1][NUMBS+1];
int accountnumb[ACCOUNTS];
double transactionc[NUMBS];
double transactiond[NUMBS];
FILE *fp, *fp1;

What is NUMBS? What is fp1? Are you sure fp1 is a valid file pointer and not NULL or uninitialized? Does I ever go beyond NUMBS? On first glance this looks correct, but if the arrays aren't large enough, you could start mangling local variables and stack frames when you exceed them...

I would say your quickest method of finding your issue is to compile the program with debugging enabled ("-g"), run the program , wait for the core-dump. Then load the program up in a debugger, against the core. For example gdb:

Code:

gdb ./prog ./core

If you type "where" it will tell you the line number it is core-dumping. You can then print out the variables so you can tell what is the problem, for example in your snippet "i" could be less then or greater than "NUMBS" which would make it coredump.

If you havent got access to a debugger I suggest you start using "printf's" to find out where the problem is. Lines such as:

Code:

printf("%d\n",__LINE__);

can show the line where it is core-dumping. Then you can add printf's of the variables around where it core-dumps.

I hope this helps...