text: #ifndef __LIB_UNISTD_H__
  # define __LIB_UNISTD_H__
  
  #include <stddef.h>
  #include <stdint.h>
  #include <sys/types.h>
  
  // TODO: move me
  #define STDIN_FILENO	0
  #define STDOUT_FILENO	1
  #define STDERR_FILENO	2
  
  //TODO: move me
  #define _SC_PAGE_SIZE	0
  #define _SC_PAGESIZE	_SC_PAGE_SIZE
  
  
  // Process part
  extern pid_t getpid(void);
  extern pid_t getpgid(void);
  extern pid_t getppid(void);
  extern int setpgid(pid_t pid, pid_t pgid);
  extern pid_t fexecve(const char *pathname, char **argv, char **envp);
  
  // File part
  extern ssize_t write(int fd, const void *buf, size_t count);
  extern ssize_t read(int fd, void *buf, size_t count);
  extern off_t lseek(int fd, off_t offset, int whence);
  extern int close(int fd);
  
  // System part
  extern long sysconf(int name);
  
  #endif /*__LIB_UNISTD_H__*/
  