1#include <sys/types.h>
 2
 3struct string;
 4
 5void osgetcwd(char *, size_t);
 6/* changes the working directory to the given path */
 7void oschdir(const char *);
 8/* creates all the parent directories of the given path */
 9int osmkdirs(struct string *, _Bool);
10/* queries the mtime of a file in nanoseconds since the UNIX epoch */
11int64_t osmtime(const char *);
12/* queries the number of online processors */
13long osnproc(void);
14/* spawn a child process */
15pid_t osspawn(char *const argv[], int fd);