1941 return wcs.err->status;
1944 In
this example,
if an error was generated in one of the
prjset() functions,
1945 wcsperr() would print an error traceback starting with
wcsset(), then
1946 celset(), and finally the particular projection-setting function that
1947 generated the error. For each of them it would print the status return value,
1948 function name, source file, line number, and an error message which may be
1949 more specific and informative than the general error messages reported in the
1950 first example. For example, in response to a deliberately generated error,
1951 the @c twcs test program, which tests
wcserr among other things, produces a
1952 traceback similar to this:
1954 ERROR 5 in wcsset() at line 1564 of file wcs.c:
1955 Invalid parameter value.
1956 ERROR 2 in celset() at line 196 of file cel.c:
1957 Invalid projection parameters.
1958 ERROR 2 in
bonset() at line 5727 of file prj.c:
1959 Invalid parameters for Bonne's projection.
1962 Each of the @ref structs "structs" in @ref overview "WCSLIB" includes a
1963 pointer, called @a err, to a
wcserr struct. When an error occurs, a struct is
1964 allocated and error information stored in it. The
wcserr pointers and the
1965 @ref memory "memory" allocated for them are managed by the routines that
1969 example above. If enabled, when an error occurs it is the user's
1970 responsibility to free the memory allocated for the error message using
1972 out of scope will result in memory leaks (if execution continues beyond the