+/*
+=item im_push_errorf(ctx, code, char const *fmt, ...)
+=synopsis im_push_errorf(aIMCTX, errno, "Cannot open file %s: %d", filename, errno);
+=category Error handling
+
+A version of im_push_error() that does printf() like formatting.
+
+Does not support perl specific format codes.
+
+=cut
+*/