sds sdstrim(sds s, const char *cset);
sds sdsrange(sds s, int start, int end);
void sdsupdatelen(sds s);
+void sdsclear(sds s);
int sdscmp(sds s1, sds s2);
sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count);
void sdsfreesplitres(sds *tokens, int count);