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more::io::lock_file Struct Reference

A handle to a lock file. More...

#include <lock_file.h>

Inheritance diagram for more::io::lock_file:

[legend]Collaboration diagram for more::io::lock_file:

[legend]List of all members.

Public Methods

• lock_file ()

  Construct an undefined lock file handle. More...
  
  

• lock_file (std::string path)

  Construct a handle for a named lock file, but do not create the file yet. More...
  
  

• ~lock_file ()

  Calls unlock(). More...
  
  

• void set_file_name (std::string)

  Set or change the file name of the lock. More...
  
  

• access_t access () const

  Return the current access of the lock. More...
  
  

• bool adjust (access_t access)

  Try to obtain the lock without blocking, and return true if successful. More...
  
  

• bool aquire (access_t acc)

  Return adjust(acc | access()). More...
  
  

• bool aquire (access_t access, double t, double dt=1.0)

  Attempt every dt seconds for t seconds to aquire(access). More...
  
  

• bool aquire (access_t access, infinite_tag, double dt=1.0)

  Attempt every dt seconds indefinitely to aquire(access). More...
  
  

• void release (access_t access=access_rw)

  Release all access. More...
  
  

• void swap (lock_file &lk)

  Swap two locks. More...
  
  

• void unlock ()

  \depreciated Same ass release(). More...
  
  

• lock_file (std::string path, bool blocking)

  \depreciated Use another constructor. More...
  
  

• bool have_lock () const

  \depreciated Use access(). More...
  
  

• void lock (std::string path, bool blocking)

  \depreciated Establish the lock with the given file name. More...
  
  

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Detailed Description

A handle to a lock file.

Read-only locks are not NFS safe (TODO). A workaround is to use access_rw also when only read access is needed.

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Constructor & Destructor Documentation

more::io::lock_file::lock_file (    )  [inline]

Construct an undefined lock file handle.

more::io::lock_file::lock_file (  std::string    path )  [inline, explicit]

Construct a handle for a named lock file, but do not create the file yet.

more::io::lock_file::~lock_file (    )  [inline]

Calls unlock().

more::io::lock_file::lock_file (  std::string    path, bool    blocking )  [inline]

\depreciated Use another constructor. Construct a handle and create the lock file with the given name if possible. If blocking=true it will hang until it manages to create the lock.

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Member Function Documentation

access_t more::io::lock_file::access (    )  const [inline]

Return the current access of the lock.

bool more::io::lock_file::adjust (  access_t    access )

Try to obtain the lock without blocking, and return true if successful. The valid arguments for access are access_none, which causes an unlock, access_r which gives read access, and access_rw which gives read write access. In addition access_w will be changed to access_rw.

bool more::io::lock_file::aquire (  access_t    access, infinite_tag   , double    dt = 1.0 )

Attempt every dt seconds indefinitely to aquire(access). See adjust(access_t) for constraint on access.

bool more::io::lock_file::aquire (  access_t    access, double    t, double    dt = 1.0 )

Attempt every dt seconds for t seconds to aquire(access). Return true if the lock was obtained. See adjust(access_t) for constraint on access.

bool more::io::lock_file::aquire (  access_t    acc )  [inline]

Return adjust(acc | access()).

bool more::io::lock_file::have_lock (    )  const [inline]

\depreciated Use access(). Returns true after successful locking and before unlock().

void more::io::lock_file::lock (  std::string    path, bool    blocking )

\depreciated Establish the lock with the given file name.

void more::io::lock_file::release (  access_t    access = access_rw )

Release all access. This function should ideally neither hang nor fail. In the case of read-only locks, however, it may in exceptional cases hang for a few seconds, and possibly fail. This may be the case if another program was interrupted at the critical stage while adjusting its own read-only lock, or if the lock files were tampered with.

void more::io::lock_file::set_file_name (  std::string    )

Set or change the file name of the lock. This causes an unlock.

void more::io::lock_file::swap (  lock_file &    lk )  [inline]

Swap two locks.

void more::io::lock_file::unlock (    )  [inline]

\depreciated Same ass release().

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The documentation for this struct was generated from the following file:

• more/io/lock_file.h

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