NAME

       ibv_get_device_list, ibv_free_device_list - get and release list of available RDMA devices

SYNOPSIS

              #include <infiniband/verbs.h>

              struct ibv_device **ibv_get_device_list(int *num_devices);

              void ibv_free_device_list(struct ibv_device **list);

DESCRIPTION

       ibv_get_device_list() returns a NULL-terminated array of RDMA devices currently available.
       The argument num_devices is optional; if not NULL, it is set  to  the  number  of  devices
       returned in the array.

       ibv_free_device_list() frees the array of devices list returned by ibv_get_device_list().

RETURN VALUE

       ibv_get_device_list()  returns  the  array  of  available  RDMA devices, or sets errno and
       returns NULL if the request fails.  If no devices are found then num_devices is set to  0,
       and non-NULL is returned.

       ibv_free_device_list() returns no value.

ERRORS

       EPERM  Permission denied.

       ENOSYS No kernel support for RDMA.

       ENOMEM Insufficient memory to complete the operation.

NOTES

       Client  code  should  open all the devices it intends to use with ibv_open_device() before
       calling ibv_free_device_list().  Once it frees the array with  ibv_free_device_list(),  it
       will  be able to use only the open devices; pointers to unopened devices will no longer be
       valid.

       Setting the environment variable IBV_SHOW_WARNINGS will cause warnings to  be  emitted  to
       stderr  if  a kernel verbs device is discovered, but no corresponding userspace driver can
       be found for it.

STATIC LINKING

       If libibverbs is statically linked to the application then all provider drivers must  also
       be  statically linked.  The library will not load dynamic providers when static linking is
       used.

       To link the providers set the RDMA_STATIC_PROVIDERS define to the comma separated list  of
       desired  providers  when  compiling  the  application.   The  special  keyword  `all' will
       statically link all supported libibverbs providers.

       This is intended to be used along  with  pkg-config(1)  to  setup  the  proper  flags  for
       libibverbs linking.

       If this is not done then ibv_get_device_list will always return an empty list.

       Using only dynamic linking for libibverbs applications is strongly recommended.

SEE ALSO

       ibv_fork_init(3), ibv_get_device_guid(3), ibv_get_device_name(3), ibv_get_device_index(3),
       ibv_open_device(3)

AUTHOR

       Dotan Barak <dotanba@gmail.com>