#define ARGV_ARRAY_INIT { empty_argv, 0, 0 }
void argv_array_init(struct argv_array *);
-void argv_array_push(struct argv_array *, const char *);
+const char *argv_array_push(struct argv_array *, const char *);
__attribute__((format (printf,2,3)))
-void argv_array_pushf(struct argv_array *, const char *fmt, ...);
+const char *argv_array_pushf(struct argv_array *, const char *fmt, ...);
LAST_ARG_MUST_BE_NULL
void argv_array_pushl(struct argv_array *, ...);
void argv_array_pushv(struct argv_array *, const char **);