int ferror ( FILE * stream ); |
<cstdio> |
Check error indicator
Checks if the error indicator associated with stream is set, returning a value different from zero if it is.
This indicator is generaly set by a previous operation on the stream that failed.
Parameters
- stream
- Pointer to a FILE object that identifies the stream.
Return Value
If the error indicator associated with the stream was set, the function returns a nonzero value.
Otherwise, it returns a zero value.
Example
/* ferror example: writing error */
#include <stdio.h>
int main ()
{
FILE * pFile;
pFile=fopen("myfile.txt","r");
if (pFile==NULL) perror ("Error opening file");
else {
fputc ('x',pFile);
if (ferror (pFile))
printf ("Error Writing to myfile.txt\n");
fclose (pFile);
}
return 0;
}
|
This program opens an existing file called myfile.txt in read-only mode but tries to write a character to it, generating an error that is detected by ferror.
Output:
Error Writing to myfile.txt
See also
| feof | Check End-of-File indicator (function) |
| clearerr | Clear error indicators (function) |
| perror | Print error message (function) |
