dcopy(1M)dcopy(1M)NAMEdcopy - copy HFS file system with compaction
The command copies an existing HFS file system (source_fs) to a new HFS
file system (destination_fs), appropriately sized to hold the reorga‐
nized results. For best results, the source file system should be a
raw device, and the destination file system should be a block device.
Always run on unmounted file systems. (In the case of the root file
system, copy it to a new minidisk.)
If no options are specified, copies files from source_fs, compressing
directories by removing vacant entries and spacing consecutive blocks
in a file by the optimal rotational gap. If options such as or are
specified, the destination file system structure will be different from
that of the source file system.
makes the destination file system identical to the source file system
and preserves the pack and volume labels. Thus, to compress a file
system without moving it, use to copy the files to another file system
and the command to copy the file back (see dd(1)).
Directory compression is accomplished by running on the primary copy of
the file system and allowing the modified directories to propagate to
the other copies of the file system in the normal manner.
recognizes the following options:
Move subdirectories to the beginning of directories.
Specify the file system size
(fsize) and inode-list size (isize) in blocks.
If this option is not specified, the source file-
system value is used.
Specify the HFS file system type.
The type of a file system can be determined with
the command (see fstyp(1M)). See
Supply device information
for creating the best organization of blocks in a
file. cyl is the number of block per cylinder;
skip is the number of blocks to skip.
Report size of source and destination file system.
Echo the completed command line, but performs no other actions.
The command line is generated by incorporating
the user-specified options and other information
derived from This option allows you to verify the
can be executed with or without options. If no options are specified
as in this example, the source and destination file systems are identi‐
cal. Any differences between the two file systems lie only in the
available disk space.
If options are specified, expect a major difference between the source
and destination file system structure:
produces invalid results if run on a mounted file system.
The figures specified in option arguments cannot be smaller than corre‐
sponding figures in the source file system.
only operates on HFS file systems.
was developed by HP.
SEE ALSOdd(1), fstyp(1M), disk(7).