Provided by: linuxcnc-uspace_2.9.1-2ubuntu1_amd64 bug

NAME

       hal_type_t - typedefs for HAL datatypes

DESCRIPTION

       typedef ... hal_bool;
              A type which may have a value of 0 or nonzero.

       typedef ... hal_bit_t;
              A volatile type which may have a value of 0 or nonzero.

       typedef ... hal_s32_t;
              A volatile type which may have a value from -2147483648 to 2147483647.

       typedef ... hal_u32_t;
              A volatile type which may have a value from 0 to 4294967295.

       typedef ... hal_port_t;
              A volatile handle to a port object. Used with hal_port* functions.

       typedef ... hal_float_t;
              A volatile floating-point type, which typically has the same precision and range as
              the C type double.

       typedef ... real_t;
              A nonvolatile floating-point type with at least as much precision as hal_float_t.

       typedef ... ireal_t;
              A nonvolatile unsigned integral type the same size as hal_float_t.

       typedef enum hal_type_t;

              HAL_BIT
                     Corresponds to the type hal_bit_t.

              HAL_FLOAT
                     Corresponds to the type hal_float_t.

              HAL_S32
                     Corresponds to the type hal_s32_t.

              HAL_U32
                     Corresponds to the type hal_u32_t.

NOTES

       hal_bit_t is typically a typedef to an integer type whose range is larger than just 0  and
       1.   When  testing  the  value  of  a hal_bit_t, never compare it to 1.  Prefer one of the
       following:

              •   if(b)

              •   if(b != 0)

       It is often useful to refer to a type that can represent all the values as a HAL type, but
       without the volatile qualifier.  The following types correspond with the HAL types:

              hal_bit_t       int

              hal_s32_t       __s32

              hal_u32_t       __u32

              hal_float_t     hal_real_t

              hal_port_t      int

       Take  care not to use the types s32 and u32.  These will compile in kernel modules but not
       in userspace, and not for realtime components when using uspace realtime.

SEE ALSO

       hal_pin_new(3hal), hal_param_new(3hal)