NAME

       xdf_closest_type - Returns a compatible data type

SYNOPSIS

       #include <xdfio.h>

       int xdf_closest_type(struct xdf* xdf, enum xdftype target);

DESCRIPTION

       xdf_closest_type()  selects  among  the data types supported by the file referenced by xdf
       the type that is the closest to the target argument. The selected type can then be  safely
       used in a call to xdf_set_chconf(3) with the XDF_CF_STOTYPE field.

       The  selection  algorithm  is based on the 3 following criterions (cited by priority, i.e.
       most important cited first): data size, signed/unsigned  type,  float/integer  value.  The
       data  size  criterion  forces  the  selected  type  to have a data size (number of byte to
       represent the value) equal or bigger than the one of the target type  (with  a  preference
       with  sizes  the  closest  to  the size of target). The signed/unsigned criterion tries to
       select a type that has the same signeness (signed or unsigned data type)  as  the  target.
       Finally  the  float/integer  criterion  tries to select a floating point type if target is
       float or double or an integer data type if target is an integer type.

       As a consequence, if target is supported  by  the  underlying  file  format  of  xdf,  the
       function is ensured to return target.

RETURN VALUE

       xdf_closest_type()  returns  the  selected  data type in case of success, otherwise -1 and
       errno is set appropriately.

ERRORS

       EINVAL the xdf pointer is NULL, or the argument type is not  an  admissible  enum  xdftype
              value.

SEE ALSO

       xdf_set_chconf(3)