fsctl.2 (2010 09)

fsctl(2) fsctl(2)

with a NULL character. The maximum size of the volume set ID is 128 bytes, so

a length of 129 can be used for outlen and the size of outbuf .

EXAMPLES

The following code fragment gets the extended attribute record for a ﬁle on a CDFS volume. The

ﬁlename is passed in as the ﬁrst argument to the routine. Note that error checking is omitted for brevity.

#include <sys/types.h>

#include <sys/vfs.h>

#include <fcntl.h>

#include <sys/cdfsdir.h>

main(argc, argv)

int argc;

char *argv[];

{

int fildes, size = 0;

char *malloc(), *outbuf;

struct statfs buf;

struct cddir cdrec;

struct cdxar_iso *xar;

statfs(argv[1], &buf); /* get logical block size */

fildes = open(argv[1], O_RDONLY); /* open file arg */

/* get directory record for file arg */

fsctl(fildes, CDFS_DIR_REC, &cdrec, sizeof(cdrec));

size = buf.f_bsize * cdrec.cdd_min.mincdd_xar_len; /* compute size */

if(size) { /* if size != 0 then there is an xar */

outbuf = malloc(size); /* malloc sufficient memory */

fsctl(fildes, CDFS_XAR, outbuf, size); /* get xar */

xar = (struct cdxar_iso *)outbuf; /* cast outbuf to access fields */

}

RETURN VALUE

fsctl() returns the number of bytes read if successful. If an error occurs, − 1 is returned and errno

is set to indicate the error.

ERRORS

fsctl() fails if any of the following conditions are encountered:

[EBADF] ﬁldes is not a valid open ﬁle descriptor.

[EFAULT] outbuf points to an invalid address.

[ENOENT] The requested information does not exist.

[EINVAL] command is not a valid command.

[EINVAL] ﬁldes does not refer to a CDFS ﬁle system.