What is FILE in C?
Consider:
#include <stdio.h>
FILE * fopen(const char *restrict filename, const char *restrict mode);fopen gives us a FILE, but what is a FILE?
First, FILE used to be a macro, which is why it’s capitalized.
Nowadays, it’s a typedef, defined in stdio.h. On macOS, in /usr/include/stdio.h:
typedef struct __sFILE {
short _file; /* fileno, if Unix descriptor, else -1 */
// ... more stuff ...
} FILE;The rest of the definition has some buffers for doing getc, ungetc, etc.
Tagged #c, #programming.
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