linux - How to use shm_open to open an existing Shared Memory object -

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If I do not exit, then I do not want to create a new shared memory object but return an error in this situation. I want to be open only if it already exists.

Read & amp; .

If shm_open is not given this O_CREAT flag will fail if the name does not exist, as does it. If O_CREAT and O_EXCL are given, it may also fail if the name exists that is said to be what happens with this failure :

ENOENT shm_open () A name was attempted that did not exist, and O_CREAT was not specified.

EEXIST both O_CREAT and O_EXCL were specified for shm_open () and the named memory object specified by name already exists.

On some Linux systems, you will learn about / dev / shm / current POSIX shared memory segment.


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