gfapi.py 文件源码

def read(self, size=-1):
        """
        Read at most size bytes from the file.

        :param buflen: length of read buffer. If less than 0, then whole
                       file is read. Default is -1.
        :returns: buffer of 'size' length
        """
        if size < 0:
            size = self.fgetsize()
        rbuf = ctypes.create_string_buffer(size)
        ret = api.glfs_read(self.fd, rbuf, size, 0)
        if ret > 0:
            # In python 2.x, read() always returns a string. It's really upto
            # the consumer to decode this string into whatever encoding it was
            # written with.
            return rbuf.value[:ret]
        elif ret < 0:
            err = ctypes.get_errno()
            raise OSError(err, os.strerror(err))