1IBV_FORK_INIT(3)        Libibverbs Programmer's Manual        IBV_FORK_INIT(3)
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NAME

6       ibv_fork_init - initialize libibverbs to support fork()
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SYNOPSIS

9       #include <infiniband/verbs.h>
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11       int ibv_fork_init(void);
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DESCRIPTION

14       ibv_fork_init()  initializes  libibverbs's  data  structures  to handle
15       fork() function calls correctly  and  avoid  data  corruption,  whether
16       fork() is called explicitly or implicitly (such as in system()).
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18       It  is not necessary to use this function if all parent process threads
19       are always blocked until all child processes end or change address spa‐
20       ces via an exec() operation.
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RETURN VALUE

23       ibv_fork_init()  returns 0 on success, or the value of errno on failure
24       (which indicates the failure reason).
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NOTES

27       ibv_fork_init() works on Linux  kernels  supporting  the  MADV_DONTFORK
28       flag for madvise() (2.6.17 and higher).
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30       Setting  the  environment variable RDMAV_FORK_SAFE or IBV_FORK_SAFE has
31       the same effect as calling ibv_fork_init().
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33       Calling ibv_fork_init() will reduce performance due to an extra  system
34       call for every memory registration, and the additional memory allocated
35       to track memory regions.  The precise performance impact depends on the
36       workload and usually will not be significant.
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SEE ALSO

39       fork(2), system(3), ibv_get_device_list(3)
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AUTHORS

42       Dotan Barak <dotanb@mellanox.co.il>
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46libibverbs                        2006-10-31                  IBV_FORK_INIT(3)