Shmget file exists

In fact I'd bet it's one of the functions mentioned in the "See Also" section of the multiple man pages I already linked you to, whose name likely starts with shm. Show 5 more comments.

Active Oldest Votes. Answerifying the various comments. When you call: shmget If you only use: shmget Improve this answer. Add a comment. Denny Mathew Denny Mathew 8 8 silver badges 13 13 bronze badges. Well when i remove this it's work! What is the importance of this? Which is usually the expectation when you don't want to fetch a previously created one explicitly.

Here, using the flag wasn't the cause of your problem, it's what made it manifest. In effect, it helped you catch a bug - shared memory not being created by the process you think is creating it - instead of having your program silently do what's potentially the wrong thing. It probably doesn't matter in homework, but generally when dealing with concurrency, you want shared resources to be accessed in precisely the way you expect them to be accessed.

In fact, that's the whole point of synchronization. Hence also my This answer suggests a hackish, potentially dangerous workaround instead of getting at the root of the issue. Sign up or log in Sign up using Google. More information Select [Diagnostics FCM Information] from the fcmconsole main menu to display the location and version of the components library in use. Using a bit version of the components library with a bit executable or vice-versa.

Missing libgfortran. E flcomp. Solution Our usual recommendation is to disable SELinux. Probable cause Model not configured to work with vis-opengl. More information This is not a fatal error. Network communications If you are using netflc to synchronize data across multiple hosts, the following shell commands are useful: netflc -v to see what netflc is doing.

Probable cause This can occur when there is no default network route. Solution See Multicast routing for details. More information To test, run netstat -r from the shell prompt. The output should contain something similar to: If both the ' default ' and ' Multicast routing You may need to run the following to configure multicast routing: Under Linux distributions with iputils2 , run: ip route add If all hosts are on a single IP local area network, communication should work automatically.

However, if multiple LANs are involved, further configuration is required. It works when I change the second shmget to:. Permission modes need to be specified in octal , not hexadecimal.

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Viewed 4k times. I have a strange problem with shared memory. Improve this question. Piotr Zierhoffer Piotr Zierhoffer 5, 1 1 gold badge 37 37 silver badges 57 57 bronze badges. Add a comment.