ferror
Header: <stdio.h>
Checks the given stream for errors.
# Declarations
int ferror( FILE *stream );
# Parameters
stream: the file stream to check
# Return value
Nonzero value if the file stream has errors occurred, 0 otherwise
# Example
#include <stdio.h>
#include <stdlib.h>
#include <locale.h>
#include <wchar.h>
int main(void)
{
char* fname = tmpnam(NULL);
FILE* f = fopen(fname, "wb");
fputs("\xff\xff\n", f); // not a valid UTF-8 character sequence
fclose(f);
setlocale(LC_ALL, "en_US.utf8");
f = fopen(fname, "rb");
wint_t ch;
while ((ch=fgetwc(f)) != WEOF) // attempt to read as UTF-8 fails
printf("%#x ", ch);
if (feof(f))
puts("EOF indicator set");
if (ferror(f))
puts("Error indicator set");
}