#pragma once #include #include extern char **environ; extern pid_t getpid(void); extern int close(int fd); extern pid_t fork(void); extern int execl(const char *path, const char *arg, ...); extern int execlp(const char *file, const char *arg, ...); extern int execle(const char *path, const char *arg, ...); extern int execv(const char *path, char *const argv[]); extern int execvp(const char *file, char *const argv[]); extern int execvpe(const char *file, char *const argv[], char *const envp[]); extern void _exit(int status); extern uid_t getuid(void); extern uid_t geteuid(void); extern char * getcwd(char *buf, size_t size); extern int pipe(int pipefd[2]); extern int dup(int oldfd); extern int dup2(int oldfd, int newfd); extern pid_t tcgetpgrp(int fd); extern int tcsetpgrp(int fd, pid_t pgrp); extern ssize_t write(int fd, const void * buf, size_t count); extern ssize_t read(int fd, void * buf, size_t count); extern ssize_t readlink(const char *pathname, char *buf, size_t bufsiz); extern int chdir(const char *path); extern int fchdir(int fd); extern int isatty(int fd); extern int usleep(useconds_t usec); extern off_t lseek(int fd, off_t offset, int whence); extern int access(const char * pathname, int mode); #define STDIN_FILENO 0 #define STDOUT_FILENO 1 #define STDERR_FILENO 2 #define SEEK_SET 0 #define SEEK_CUR 1 #define SEEK_END 2