#include <db_cxx.h>
DbEnv::set_isalive(int (*is_alive)(DbEnv *dbenv, pid_t pid, 
    db_threadid_t tid, u_int32_t flags));

Declare a function that returns if a thread of control (either a true thread or a process) is still running. The DbEnv::set_isalive() method supports the DbEnv::failchk() method. For more information, see Architecting Data Store and Concurrent Data Store applications, and Architecting Transactional Data Store applications, both in the Berkeley DB Programmer's Reference Guide.

The DbEnv::set_isalive() method configures operations performed using the specified DbEnv handle, not all operations performed on the underlying database environment.

The DbEnv::set_isalive() method may be called at any time during the life of the application.

The DbEnv::set_isalive() method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.



The is_alive parameter is a function which returns non-zero if the thread of control, identified by the pid and tid arguments, is still running. The function takes four arguments:

  • dbenv

    The dbenv parameter is the enclosing database environment handle, allowing application access to the application-private fields of that object.

  • pid

    The pid parameter is a process ID returned by the function specified to the DbEnv::set_thread_id() method.

  • tid

    The tid parameter is a thread ID returned by the function specified to the DbEnv::set_thread_id() method.

  • flags

    The flags parameter must be set to 0 or the following value:


      Return only if the process is alive, the thread ID should be ignored.


The DbEnv::set_isalive() method may fail and throw a DbException exception, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:


An invalid flag value or parameter was specified.



See Also

Database Environments and Related Methods