IO之Basic IO

int creat (char *name, int flag);
int remove(char *name);

/* flags */
#define O_RDONLY   0x0000 /* open for reading only */
#define O_WRONLY   0x0001 /* open for writing only */
#define O_RDWR     0x0002 /* open for reading and writing */
#define O_APPEND   0x0008 /* writes are guaranteed at file end */
#define O_CREAT    0x0200 /* create a file if not existing */
#define O_TRUNC    0x0400 /* open with truncation */
#define O_EXCL     0x0800 /* error on open if file exists and O_CREAT is also set */
#define O_SYNC     0x2000 /* do all writes synchronously on DosFs */
#define O_NONBLOCK 0x4000 /* non blocking I/O */
#define O_NOCTTY   0x8000 /* don't assign a controlling-terminal */
#define O_DSYNC   0x10000 /* file data only integrity while writing */
#define O_RSYNC   0x20000 /* sync read operations */
int open
    (
    char *name,
    int   flags,
    int   mode  /* UNIX chmod-style file mode */
    );
int close (int fd);
int read  (int fd, char *buffer, int maxBytes);
int write (int fd, char *buffer, int nBytes);

/* ioctl function codes */
#define FIONREAD        1   /* get num chars available to read */
#define FIOFLUSH        2   /* flush any chars in buffers */
#define FIOOPTIONS      3   /* set options (FIOSETOPTIONS) */
#define FIOBAUDRATE     4   /* set serial baud rate */
#define FIODISKFORMAT   5   /* format disk */
#define FIODISKINIT     6   /* initialize disk directory */
#define FIOSEEK         7   /* set current file char position */
#define FIOWHERE        8   /* get current file char position */
#define FIODIRENTRY     9   /* return a directory entry (obsolete)*/
#define FIORENAME       10  /* rename a directory entry */
#define FIOREADYCHANGE  11  /* is there media change on the device? */
#define FIONWRITE       12  /* get num chars still to be written */
#define FIODISKCHANGE   13  /* set a media change on the device */
#define FIOCANCEL       14  /* cancel read or write on the device */
#define FIOSQUEEZE      15  /* OBSOLETED since RT11 is obsoleted */
#define FIONBIO         16  /* set non-blocking I/O; SOCKETS ONLY!*/
#define FIONMSGS        17  /* return num msgs in pipe */
#define FIOGETNAME      18  /* return file name in arg */
#define FIOGETOPTIONS   19  /* get options */
#define FIOSETOPTIONS   FIOOPTIONS  /* set options */
#define FIOISATTY       20  /* is a tty */
#define FIOSYNC         21  /* sync to disk */
#define FIOPROTOHOOK    22  /* specify protocol hook routine */
#define FIOPROTOARG     23  /* specify protocol argument */
#define FIORBUFSET      24  /* alter the size of read buffer  */
#define FIOWBUFSET      25  /* alter the size of write buffer */
#define FIORFLUSH       26  /* flush any chars in read buffers */
#define FIOWFLUSH       27  /* flush any chars in write buffers */
#define FIOSELECT       28  /* wake up process in select on I/O */
#define FIOUNSELECT     29  /* wake up process in select on I/O */
#define FIONFREE        30  /* get free byte count on device */
#define FIOMKDIR        31  /* create a directory */
#define FIORMDIR        32  /* remove a directory */
#define FIOLABELGET     33  /* get volume label */
#define FIOLABELSET     34  /* set volume label */
#define FIOATTRIBSET    35  /* set file attribute */
#define FIOCONTIG       36  /* allocate contiguous space */
#define FIOREADDIR      37  /* read a directory entry (POSIX) */
#define FIOFSTATGET_OLD 38  /* get file status info - legacy */
#define FIOUNMOUNT      39  /* unmount disk volume */
#define FIOSCSICOMMAND  40  /* issue a SCSI command */
#define FIONCONTIG      41  /* get size of max contig area on dev */
#define FIOTRUNC        42  /* truncate file to specified length */
#define FIOGETFL        43  /* get file mode, like fcntl(F_GETFL) */
#define FIOTIMESET      44  /* change times on a file for utime() */
#define FIOINODETONAME  45  /* given inode number, return filename*/
#define FIOFSTATFSGET   46  /* get file system status info */
#define FIOMOVE         47  /* move file, ala mv, (mv not rename) */

/* 64-bit ioctl codes, "long long *" expected as 3rd argument */
#define FIOCHKDSK       48
#define FIOCONTIG64     49
#define FIONCONTIG64    50
#define FIONFREE64      51
#define FIONREAD64      52
#define FIOSEEK64       53
#define FIOWHERE64      54
#define FIOTRUNC64      55

#define FIOCOMMITFS     56
#define FIODATASYNC     57  /* sync to I/O data integrity */
#define FIOLINK         58  /* create a link */
#define FIOUNLINK       59  /* remove a link */
#define FIOACCESS       60  /* support POSIX access() */
#define FIOPATHCONF     61  /* support POSIX pathconf() */
#define FIOFCNTL        62  /* support POSIX fcntl() */
#define FIOCHMOD        63  /* support POSIX chmod() */
#define FIOFSTATGET     64  /* get stat info - POSIX  */
#define FIOUPDATE       65  /* update dosfs default create option */

/* These are for HRFS but can be used for other future file systems */
#define FIOCOMMITPOLICYGETFS 66 /* get the file system commit policy */
#define FIOCOMMITPOLICYSETFS 67 /* set the file system commit policy */
#define FIOCOMMITPERIODGETFS 68 /* get periodic commit interval in ms */
#define FIOCOMMITPERIODSETFS 69 /* set the file system's periodic  */
#define FIOFSTATFSGET64      70 /* get file system status info */

/* the next two ioctls are for block-type storage media (e.g., disks) */
#define FIODISCARDGET   70  /* does hardware want DISCARDs? - for xbdIoctl()*/
#define FIODISCARD      71  /* mark sectors (sectorRange) as deleted */

#define FIOREADDIRPLUS  72  /* read a directory entry extention  */

int ioctl (int fd, int function,...);