NAME    [Toc]    [Back]

     cgread, cgread1 -- read cylinder groups of UFS disks

LIBRARY    [Toc]    [Back]

     UFS File System Access Library (libufs, -lufs)

SYNOPSIS    [Toc]    [Back]

     #include <sys/param.h>
     #include <sys/mount.h>
     #include <ufs/ufs/ufsmount.h>
     #include <ufs/ufs/dinode.h>
     #include <ufs/ffs/fs.h>
     #include <libufs.h>

     int
     cgread(struct uufsd *disk);

     int
     cgread1(struct uufsd *disk, int c);

DESCRIPTION    [Toc]    [Back]

     The cgread() and cgread1() functions provide cylinder group reads for
     libufs(3) consumers.  The cgread1() function reads from one cylinder
     group, specified by c into the d_cg field of a userland UFS disk structure.
  It sets the d_lcg field to the cylinder group number c.

     The cgread() function operates on sequential cylinder groups.  Calling
     the cgread() function is equivalent to calling cgread1 with a cylinder
     group specifier equivalent to the value of the current d_ccg field, and
     then incrementing the d_ccg field.

     Both functions return 0 if there are no more cylinder groups to read, 1
     if there are more cylinder groups, and -1 on error.

ERRORS    [Toc]    [Back]

     The function cgread() may fail and set errno for any of the errors specified
 for the library function bread(3).

     The function cgread1() has semantically identical failure conditions to
     those of cgread().

SEE ALSO    [Toc]    [Back]

     bread(3), libufs(3)

HISTORY    [Toc]    [Back]

     These functions first appeared as part of libufs(3) in FreeBSD 5.1.

AUTHORS    [Toc]    [Back]

     Juli Mallett <jmallett@FreeBSD.org>


FreeBSD 5.2.1			 June 04, 2003			 FreeBSD 5.2.1