Function FreeFile

src/backend/storage/file/fd.c:2702–2723

* Close a file returned by AllocateFile. * * Note we do not check fclose's return value --- it is up to the caller * to handle close errors. */

 * to handle close errors.
 */
int
FreeFile(FILE *file)
{
	int			i;

	DO_DB(elog(LOG, "FreeFile: Allocated %d", numAllocatedDescs));

	/* Remove file from list of allocated files, if it's present */
	for (i = numAllocatedDescs; --i >= 0;)
	{
		AllocateDesc *desc = &allocatedDescs[i];

		if (desc->kind == AllocateDescFile && desc->desc.file == file)
			return FreeDesc(desc);
	}

	/* Only get here if someone passes us a file not in allocatedDescs */
	elog(WARNING, "file passed to FreeFile was not obtained from AllocateFile");
	Assert(false);

	return fclose(file);
}

/*
 * Close a file returned by OpenTransientFile.