1951 return wcs.err->status;
1954 In
this example,
if an error was generated in one of the
prjset() functions,
1955 wcsperr() would print an error traceback starting with
wcsset(), then
1956 celset(), and finally the particular projection-setting function that
1957 generated the error. For each of them it would print the status return value,
1958 function name, source file, line number, and an error message which may be
1959 more specific and informative than the general error messages reported in the
1960 first example. For example, in response to a deliberately generated error,
1961 the @c twcs test program, which tests
wcserr among other things, produces a
1962 traceback similar to this:
1964 ERROR 5 in wcsset() at line 1564 of file wcs.c:
1965 Invalid parameter value.
1966 ERROR 2 in celset() at line 196 of file cel.c:
1967 Invalid projection parameters.
1968 ERROR 2 in
bonset() at line 5727 of file prj.c:
1969 Invalid parameters for Bonne's projection.
1972 Each of the @ref structs "structs" in @ref overview "WCSLIB" includes a
1973 pointer, called @a err, to a
wcserr struct. When an error occurs, a struct is
1974 allocated and error information stored in it. The
wcserr pointers and the
1975 @ref memory "memory" allocated for them are managed by the routines that
1979 example above. If enabled, when an error occurs it is the user's
1980 responsibility to free the memory allocated for the error message using
1982 out of scope will result in memory leaks (if execution continues beyond the