The debug_fclose() WordPress PHP function is used to close the debugging file handle.
Usage
This is a simple use case:
debug_fclose($fp);
In the above example, $fp is a file pointer which we want to close.
Parameters
- $fp (mixed): This parameter is required, although it is not used within the function.
More information
See WordPress Developer Resources: debug_fclose()
This function is rarely used and might be deprecated in the future. Its source code can be found in the WordPress core files.
Examples
Closing a File Handle
$fp = fopen('debug.txt', 'w');
fwrite($fp, "Debugging Information");
debug_fclose($fp);
This code opens a file called debug.txt, writes “Debugging Information” to it, and then closes the file using the debug_fclose() function.
Preventing Further Writes
$fp = fopen('debug.txt', 'w');
fwrite($fp, "First line");
debug_fclose($fp);
fwrite($fp, "Second line");
In this example, after writing the first line to the file, debug_fclose() is used to close the file. Any subsequent write attempts, like the “Second line”, will fail.
Checking If File Is Open
$fp = fopen('debug.txt', 'w');
if (is_resource($fp)) {
fwrite($fp, "Debugging Information");
debug_fclose($fp);
}
This code checks if the file is open (i.e., $fp is a resource) before attempting to write to it and close it.
Multiple Close Attempts
$fp = fopen('debug.txt', 'w');
fwrite($fp, "Debugging Information");
debug_fclose($fp);
debug_fclose($fp);
In this example, debug_fclose() is called twice on the same file handle. The second call will have no effect as the file is already closed.
Closing a Null Handle
$fp = null; debug_fclose($fp);
This code attempts to close a null file handle. The debug_fclose() function will simply do nothing in this case.