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d S)� PIDLockFileaA Lockfile implemented as a Unix PID file.
The lock file is a normal file named by the attribute `path`.
A lock's PID file contains a single line of text, containing
the process ID (PID) of the process that acquired the lock.
>>> lock = PIDLockFile('somefile')
>>> lock = PIDLockFile('somefile')
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t | j � S)z- Get the PID from the lock file.
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r r r �read_pid* s zPIDLockFile.read_pidc C s t j j | j � S)zv Test if the lock is currently held.
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r r r � is_locked/ s zPIDLockFile.is_lockedc C s" | j � o! t j � | j � k S)z� Test if the lock is held by the current process.
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r r r � i_am_locking7 s zPIDLockFile.i_am_lockingc C s/ | d k r | n | j } t j � } | d k rI | d k rI | | 7} x� y t | j � Wn� t k
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d | j � � WYd d } ~ XqL Xd SqL Wd S)z� Acquire the lock.
Creates the PID file for this lock, or raises an error if
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&&zPIDLockFile.acquirec C sO | j � s t d | j � � | j � s> t d | j � � t | j � d S)z� Release the lock.
Removes the PID file to release the lock, or raises an
error if the current process does not hold the lock.
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zPIDLockFile.releasec C s t | j � d S)z� Break an existing lock.
Removes the PID file if it already exists, otherwise does
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rd Yn X| j � | S)z� Read the PID recorded in the named PID file.
Read and return the numeric PID recorded as text in the named
PID file. If the PID file cannot be read, or if the content is
not a valid PID, return ``None``.
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r c C so t j t j Bt j B} d } t j | | | � } t j | d � } t j � } | j d | � | j � d S)u� Write the PID in the named PID file.
Get the numeric process ID (“PID”) of the current process
and write it to the named file as a line of text.
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rP } z | j t j k r; n � WYd d } ~ Xn Xd S)z� Remove the named PID file if it exists.
Removing a PID file that doesn't already exist puts us in the
desired state, so we ignore the condition if the file does not
exist.
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