Optimal lock file method

by

Take a look at the enlightening presentation File Locking Tricks and Traps:

This short talk presents several common pitfalls of file locking and a few useful tricks for using file locking more effectively.

Edit: To address your questions more precisely:

Is there a better synchronization method than the lock file?

As @Hasturkun already mentioned and as the presentation above told, the system call you need to use is flock(2). If the resource you’d like to share across many users is already file-based (in your case it is /dev/ttyUSBx), then you can flock the device file itself.

How to determine if the process who created the lock file is still running?

You don’t have to determine this, as the flock-ed lock will be automatically released upon closing the file descriptor associated with your file, even if the process was terminated.

How making it possible for another user to remove the lock file if not in use?

If you would lock the device file itself, then there will be no need to remove the file. Even if you would decide to lock an ordinary file in /var/lock, with flock you will not need to remove the file in order to release the lock.

More Related Contents:

  1. How do I rename a file with a string using the rename() function (c++)? [closed]
  2. How do I print the content of a file?
  3. Fastest way to check if a file exists using standard C++/C++11,14,17/C?
  4. Reading and writing binary file
  5. Reader/Writer Locks in C++
  6. Read Unicode UTF-8 file into wstring
  7. Create a directory if it doesn’t exist
  8. How to embed a file into an executable?
  9. C++ string to double conversion
  10. How to set file permissions (cross platform) in C++?
  11. Is there a LINQ library for C++? [closed]
  12. Child process receives parent’s SIGINT
  13. C++ Filehandling: Difference between ios::app and ios::ate?
  14. Simple glob in C++ on unix system?
  15. practical examples use dup or dup2
  16. fork() and output
  17. What’s the least invasive way to read a locked file in C# (perhaps in unsafe mode)?
  18. How to easily make std::cout thread-safe?
  19. c++ template and header files [duplicate]
  20. Is it ok to read a shared boolean flag without locking it when another thread may set it (at most once)?
  21. Write a file in a specific path in C++
  22. how to show enter password in the form of Asterisks(*) on terminal
  23. Create a function to check for key press in Unix using ncurses
  24. How to use lock in OpenMP?
  25. gprof reports no time accumulated
  26. Creating Library with backward compatible ABI that uses Boost
  27. Difference between opening a file in binary vs text [duplicate]
  28. Where does one get the “sys/socket.h” header/source file?
  29. Is it possible to use threads to speed up file reading?
  30. Why does wide file-stream in C++ narrow written data by default?

Leave a Comment