3275     return wcs.err->status;
 
 3278 In 
this example, 
if an error was generated in one of the 
prjset() functions,
 
 3279 wcsperr() would print an error traceback starting with 
wcsset(), then
 
 3280 celset(), and finally the particular projection-setting function that
 
 3281 generated the error.  For each of them it would print the status return value,
 
 3282 function name, source file, line number, and an error message which may be
 
 3283 more specific and informative than the general error messages reported in the
 
 3284 first example.  For example, in response to a deliberately generated error,
 
 3285 the @c twcs test program, which tests 
wcserr among other things, produces a
 
 3286 traceback similar to this:
 
 3288 ERROR 5 in wcsset() at line 1564 of file wcs.c:
 
 3289   Invalid parameter value.
 
 3290 ERROR 2 in celset() at line 196 of file cel.c:
 
 3291   Invalid projection parameters.
 
 3292 ERROR 2 in 
bonset() at line 5727 of file prj.c:
 
 3293   Invalid parameters for Bonne's projection.
 
 3296 Each of the @ref structs "structs" in @ref overview "WCSLIB" includes a
 
 3297 pointer, called @a err, to a 
wcserr struct.  When an error occurs, a struct is
 
 3298 allocated and error information stored in it.  The 
wcserr pointers and the
 
 3299 @ref memory "memory" allocated for them are managed by the routines that
 
 3303 example above.  If enabled, when an error occurs it is the user's
 
 3304 responsibility to free the memory allocated for the error message using
 
 3306 out of scope will result in memory leaks (if execution continues beyond the
 
int wcsfree(struct wcsprm *wcs)
Destructor for the wcsprm struct. 
int wcserr_enable(int enable)
Enable/disable error messaging. 
Error message handling. 
Definition: wcserr.h:225
int prjfree(struct prjprm *prj)
Destructor for the prjprm struct. 
int wcsset(struct wcsprm *wcs)
Setup routine for the wcsprm struct. 
int celfree(struct celprm *cel)
Destructor for the celprm struct. 
int wcsprintf_set(FILE *wcsout)
Set output disposition for wcsprintf() and wcsfprintf(). 
int wcsperr(const struct wcsprm *wcs, const char *prefix)
Print error messages from a wcsprm struct. 
int prjset(struct prjprm *prj)
Generic setup routine for the prjprm struct. 
int bonset(struct prjprm *prj)
Set up a prjprm struct for Bonne's (BON) projection. 
int wcsini(int alloc, int naxis, struct wcsprm *wcs)
Default constructor for the wcsprm struct. 
int celset(struct celprm *cel)
Setup routine for the celprm struct.