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Comments on Why does fopen return NULL?
Parent
Why does fopen return NULL?
#include<stdio.h>
#include<stdlib.h>
int main (void){
FILE *cfPtr;
char name[15];
int ID;
if ((cfPtr = fopen("draft.txt","w")) == NULL){
printf("File could not be opened...\n"); //program gives me this as an output
}
}
Output:
File could not be opened...
Post
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The simple explanation would be that you simply don't have write access to the path, which is one possibility.
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Another weird phenomenon that may happen is that you are running a very old C compiler and it can't find
fopen- because you did forget to#include <stdio.h>.When this happens on modern compilers, you get a compiler error. On very old compilers (the "ANSI/C90 standard") the compiler would instead cook up some dumb initiative of its own and treat the function as if it returns
int. This could create very strange and subtle bugs.You could avoid such bugs by updating to the latest version of your C compiler. In case of gcc, clang or icc compilers you should also follow this advise: What compiler options are recommended for beginners learning C?
Unrelated to your question fflush(stdin); is undefined behavior and rarely the correct solution. Instead you should just ensure to consume the line feed character after taking the input. (For example by a getchar() call or by adding a space at the beginning of the scanf format string - but this is a topic for another thread.)
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