58 lines
2.0 KiB
ReStructuredText
58 lines
2.0 KiB
ReStructuredText
|
|
:mod:`linecache` --- Random access to text lines
|
|
================================================
|
|
|
|
.. module:: linecache
|
|
:synopsis: This module provides random access to individual lines from text files.
|
|
.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
|
|
|
|
|
|
The :mod:`linecache` module allows one to get any line from any file, while
|
|
attempting to optimize internally, using a cache, the common case where many
|
|
lines are read from a single file. This is used by the :mod:`traceback` module
|
|
to retrieve source lines for inclusion in the formatted traceback.
|
|
|
|
.. seealso::
|
|
|
|
Latest version of the `linecache module Python source code
|
|
<http://svn.python.org/view/python/branches/release27-maint/Lib/linecache.py?view=markup>`_
|
|
|
|
The :mod:`linecache` module defines the following functions:
|
|
|
|
|
|
.. function:: getline(filename, lineno[, module_globals])
|
|
|
|
Get line *lineno* from file named *filename*. This function will never raise an
|
|
exception --- it will return ``''`` on errors (the terminating newline character
|
|
will be included for lines that are found).
|
|
|
|
.. index:: triple: module; search; path
|
|
|
|
If a file named *filename* is not found, the function will look for it in the
|
|
module search path, ``sys.path``, after first checking for a :pep:`302`
|
|
``__loader__`` in *module_globals*, in case the module was imported from a
|
|
zipfile or other non-filesystem import source.
|
|
|
|
.. versionadded:: 2.5
|
|
The *module_globals* parameter was added.
|
|
|
|
|
|
.. function:: clearcache()
|
|
|
|
Clear the cache. Use this function if you no longer need lines from files
|
|
previously read using :func:`getline`.
|
|
|
|
|
|
.. function:: checkcache([filename])
|
|
|
|
Check the cache for validity. Use this function if files in the cache may have
|
|
changed on disk, and you require the updated version. If *filename* is omitted,
|
|
it will check all the entries in the cache.
|
|
|
|
Example::
|
|
|
|
>>> import linecache
|
|
>>> linecache.getline('/etc/passwd', 4)
|
|
'sys:x:3:3:sys:/dev:/bin/sh\n'
|
|
|