xdot.py 文件源码

def __init__(self, buf = None, pos = 0, filename = None, fp = None):
        if fp is not None:
            try:
                fileno = fp.fileno()
                length = os.path.getsize(fp.name)
                import mmap
            except:
                # read whole file into memory
                buf = fp.read()
                pos = 0
            else:
                # map the whole file into memory
                if length:
                    # length must not be zero
                    buf = mmap.mmap(fileno, length, access = mmap.ACCESS_READ)
                    pos = os.lseek(fileno, 0, 1)
                else:
                    buf = ''
                    pos = 0

            if filename is None:
                try:
                    filename = fp.name
                except AttributeError:
                    filename = None

        self.buf = buf
        self.pos = pos
        self.line = 1
        self.col = 1
        self.filename = filename