def readline(self, length=None):
r"""Read one entire line from the file.
A trailing newline character is kept in the string (but may be absent
when a file ends with an incomplete line). If the size argument is
present and non-negative, it is a maximum byte count (including the
trailing newline) and an incomplete line may be returned.
An empty string is returned only when EOF is encountered immediately.
Note: Unlike stdio's fgets(), the returned string contains null
characters ('\0') if they occurred in the input.
"""
_complain_ifclosed(self.closed)
if self.buflist:
self.buf += ''.join(self.buflist)
self.buflist = []
i = self.buf.find('\n', self.pos)
if i < 0:
return None # rewrite the code of StringIO
else:
newpos = i+1
if length is not None and length >= 0:
if self.pos + length < newpos:
newpos = self.pos + length
r = self.buf[self.pos:newpos]
self.pos = newpos
return r
def writelines(self, iterable):
"""
writelines(iterable) -> None. Write the iterable of strings to file.
Note that newlines are not added. This is equalivalent to calling
write() for each string in the iterable.
"""
_complain_ifclosed(self.closed)
_complain_ifreadonly(self._isreadonly())
return self._file.writelines(iterable)
def write(self, str):
"""
write(str) -> None. Write string str to file.
Note that due to buffering, flush() or close() are needed before
the database reflects the data written.
"""
_complain_ifclosed(self.closed)
_complain_ifreadonly(self._isreadonly())
return self._file.write(str)
def seek(self, offset, whence=0):
"""
seek(offset[, whence]) -> None. Move to new file position.
Argument offset is a byte count. Optional argument whence defaults to
0 (offset from start of file, offset should be >= 0); other values are 1
(move relative to current position, positive or negative), and 2 (move
relative to end of file, usually negative, but allows seeking beyond
the end of a file).
"""
_complain_ifclosed(self.closed)
return self._file.seek(offset, whence)
def truncate(self, size=None):
"""
truncate([size]) -> None. Truncate the file to at most size bytes.
Size defaults to the current file position, as returned by tell().
"""
_complain_ifclosed(self.closed)
_complain_ifreadonly(self._isreadonly())
position = self._file.tell()
try:
if size is not None:
self._file.seek(size)
return self._file.truncate()
finally:
self._file.seek(position)
def isatty(self):
"""isatty() -> False."""
_complain_ifclosed(self.closed)
return False
def next(self):
_complain_ifclosed(self.closed)
r = self._file.readline()
if not r:
raise StopIteration
return r
def flush(self):
"""flush() -> None. Flush the internal I/O buffer."""
_complain_ifclosed(self.closed)
_complain_ifreadonly(self._isreadonly())
self.save()
def readlines(self):
"""readlines() -> list of strings, each a line from the file."""
_complain_ifclosed(self.closed)
return self._file.readlines()
def readline(self):
"""readline() -> next line from the file, as a string."""
_complain_ifclosed(self.closed)
return self._file.readline()
def read(self, size=-1):
"""read([size]) -> read at most size bytes, returned as a string."""
_complain_ifclosed(self.closed)
return self._file.read(size)
def tell(self):
"""
tell() -> current file position, an integer (may be a long integer).
"""
_complain_ifclosed(self.closed)
return self._file.tell()