C an ATM

[jerryandchandan]

hello. am new in this forum but i notice that u have dissucions about c so i am wondering if anyone can help me in doing an ATM program using file I/O. i know how to create a text file and use it but i dont know how to make it read one at a time. for example: this is my starting program.

#include <stdio.h>

int main()
{
FILE *customer_infor mation;
char pin_number[4]={101,102,103,1 04};
int test;
customer_inform ation=fopen("cu stomer_informat ion.txt","w");
if(customer_inf ormation==NULL)
{
puts("Error creating file");
return (1);
}

for(test=0;test <4;test++)
fprintf(custome r_information," %d\n",pin_numbe r[test]);
fclose(customer _information);

printf("Pin numbers:");
for(test=0;test <4;test++)
printf("\n%d\n" ,pin_number[test]);


return 0;

but i need this to read one number at a time like:
printf("Enter your pin number:");
the file contains: 101,102,103
but i need it to read just 101

[vmpstr]

Your file contains

101
102
103

Then you can just use fscanf(infile, "%d", &first_pin); (or some other read-from-file function, coupled with string-to-integer conversion)

Is that what you are asking?

[jerryandchandan]

i would like to use char or has a string only and not int for the pin number. could i do that and now. please.

[vmpstr]

... and now.

You can certainly do it at any point in time. Any book on C can help you read a C string (array of characters that is nul terminated) from a file.

[jerryandchandan]

i have but i dont understand the concept

[vmpstr]

You don't understand the concept of reading strings from file? What piece of code from your C book do you not understand in particular?