00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011
00012
00013
00014
00015
00016
00017
00018
00019
00020
00021
00022
00023
00024
00025
00026
00027
00028
00029
00030
00031
00032
00033
00034
00035
00036
00037
00038
00039
00040
00041
00042
00043
00044 #ifndef WCSLIB_WCSLIB
00045 #define WCSLIB_WCSLIB
00046
00047 #include "cel.h"
00048 #include "fitshdr.h"
00049 #include "lin.h"
00050 #include "log.h"
00051 #include "prj.h"
00052 #include "spc.h"
00053 #include "sph.h"
00054 #include "spx.h"
00055 #include "tab.h"
00056 #include "wcs.h"
00057 #include "wcserr.h"
00058 #include "wcsfix.h"
00059 #include "wcshdr.h"
00060 #include "wcsmath.h"
00061 #include "wcsprintf.h"
00062 #include "wcstrig.h"
00063 #include "wcsunits.h"
00064 #include "wcsutil.h"
00065
00066 #endif
00067
01936 wcserr_enable(1);
01937 wcsprintf_set(stderr);
01938
01939 ...
01940
01941 if (wcsset(&wcs) {
01942 wcsperr(&wcs);
01943 return wcs.err->status;
01944 }
01945 @endverbatim
01946 In this example, if an error was generated in one of the prjset() functions,
01947 wcsperr() would print an error traceback starting with wcsset(), then
01948 celset(), and finally the particular projection-setting function that
01949 generated the error. For each of them it would print the status return value,
01950 function name, source file, line number, and an error message which may be
01951 more specific and informative than the general error messages reported in the
01952 first example. For example, in response to a deliberately generated error,
01953 the @c twcs test program, which tests wcserr among other things, produces a
01954 traceback similar to this:
01955 @verbatim
01956 ERROR 5 in wcsset() at line 1564 of file wcs.c:
01957 Invalid parameter value.
01958 ERROR 2 in celset() at line 196 of file cel.c:
01959 Invalid projection parameters.
01960 ERROR 2 in bonset() at line 5727 of file prj.c:
01961 Invalid parameters for Bonne's projection.
01962 @endverbatim
01963
01964 Each of the @ref structs "structs" in @ref overview "WCSLIB" includes a
01965 pointer, called @a err, to a wcserr struct. When an error occurs, a struct is
01966 allocated and error information stored in it. The wcserr pointers and the
01967 @ref memory "memory" allocated for them are managed by the routines that
01968 manage the various structs such as wcsini() and wcsfree().
01969
01970 wcserr messaging is an opt-in system enabled via wcserr_enable(), as in the
01971 example above. If enabled, when an error occurs it is the user's
01972 responsibility to free the memory allocated for the error message using
01973 wcsfree(), celfree(), prjfree(), etc. Failure to do so before the struct goes
01974 out of scope will result in memory leaks (if execution continues beyond the
01975 error).
01976 */
01977
01978
02450
02451
02452
02453
02454