How a client attaches to the communications portion (UNIX)

Client-application processes that communicate with the database server through shared memory (nettype ipcshm) attach transparently to the communications portion of shared memory. System-library functions that are automatically compiled into the application enable it to attach to the communications portion of shared memory.

For information about specifying a shared-memory connection, see Client/server communication, and Network virtual processors.

If the INFORMIXSHMBASE environment variable is not set, the client application attaches to the communications portion at an address that is platform-specific. If the client application attaches to other shared-memory segments (not database server shared memory), the user can set the INFORMIXSHMBASE environment variable to specify the address at which to attach the database server shared-memory communications segments. When you specify the address at which to address the shared-memory communications segments, you can prevent the database server from colliding with the other shared-memory segments that your application uses. For information about how to set the INFORMIXSHMBASE environment variable, see the HCL OneDB™ Guide to SQL: Reference.