c - while compiling below code am getting segmentation fault can you spot me the error for me -

#include<stdio.h> #include<ctype.h> void main() {     file *fp1,*fp2,*fp3;     char a[100],b;     int i=0,j=0;     fp1=fopen("names.txt","r");     fp2=fopen("names.txt","w");     i=0;         {         b=fgetc(fp1);        b=toupper(b);        a[i]=b;         i++;     } while(b!=eof);     i=0;         {         fputc(a[i],fp2);         i++;     }while(a[i]!=eof);     fclose(fp1);     fclose(fp2);     fclose(fp3); } 

am getting segmentation fault while compiling code can u plzz me spotting error error like"line 2:segmentation fault "

you need learn how debug. either learn how use debugger, or if haven't got patience, put debug prints in code see how far getting. example:

fprintf(stderr, "%d\n", i); 

that tell something. find error pretty quickly.

my guesses are:

1. your file bigger 100 characters.
2. b should int , should not store in array.
3. the second loop should not end-of-file, should use count of number of characters read.
4. you closing fp3 haven't opened it.

but again, basic stuff. need learn basic debugging.