ack/lib/minix/include/fcntl.h
1991-09-03 11:54:28 +00:00

69 lines
2.7 KiB
C

/* The <fcntl.h> header is needed by the open() and fcntl() system calls,
* which have a variety of parameters and flags. They are described here.
* The formats of the calls to each of these are:
*
* open(path, oflag [,mode]) open a file
* fcntl(fd, cmd [,arg]) get or set file attributes
*
*/
#ifndef _FCNTL_H
#define _FCNTL_H
/* These values are used for cmd in fcntl(). POSIX Table 6-1. */
#define F_DUPFD 0 /* duplicate file descriptor */
#define F_GETFD 1 /* get file descriptor flags */
#define F_SETFD 2 /* set file descriptor flags */
#define F_GETFL 3 /* get file status flags */
#define F_SETFL 4 /* set file status flags */
#define F_GETLK 5 /* get record locking information */
#define F_SETLK 6 /* set record locking information */
#define F_SETLKW 7 /* set record locking info; wait if blocked */
/* File descriptor flags used for fcntl(). POSIX Table 6-2. */
#define FD_CLOEXEC 1 /* close on exec flag for third arg of fcntl */
/* L_type values for record locking with fcntl(). POSIX Table 6-3. */
#define F_RDLCK 0 /* shared or read lock */
#define F_WRLCK 1 /* exclusive or write lock */
#define F_UNLCK 2 /* unlock */
/* Oflag values for open(). POSIX Table 6-4. */
#define O_CREAT 00100 /* creat file if it doesn't exist */
#define O_EXCL 00200 /* exclusive use flag */
#define O_NOCTTY 00400 /* do not assign a controlling terminal */
#define O_TRUNC 01000 /* truncate flag */
/* File status flags for open() and fcntl(). POSIX Table 6-5. */
#define O_APPEND 02000 /* set append mode */
#define O_NONBLOCK 04000 /* no delay */
/* File access modes for open() and fcntl(). POSIX Table 6-6. */
#define O_RDONLY 0 /* open(name, O_RDONLY) opens read only */
#define O_WRONLY 1 /* open(name, O_WRONLY) opens write only */
#define O_RDWR 2 /* open(name, O_RDWR) opens read/write */
/* Mask for use with file access modes. POSIX Table 6-7. */
#define O_ACCMODE 03 /* mask for file access modes */
/* Struct used for locking. POSIX Table 6-8. */
struct flock {
short l_type; /* type: F_RDLCK, F_WRLCK, or F_UNLCK */
short l_whence; /* flag for starting offset */
off_t l_start; /* relative offset in bytes */
off_t l_len; /* size; if 0, then until EOF */
pid_t l_pid; /* process id of the locks' owner */
};
/* Function Prototypes. */
#ifndef _ANSI_H
#include <ansi.h>
#endif
_PROTOTYPE( int creat, (const char *_path, Mode_t _mode) );
_PROTOTYPE( int fcntl, (int _filedes, int _cmd, ...) );
_PROTOTYPE( int open, (const char *_path, int _oflag, ...) );
#endif /* _FCNTL_H */