Guralp Systems CMG-DCM - Manual (Page 117)

Operator's guide
moving files when necessary. This program ordinarily runs constantly
in the background. However, a user can use the command diskman
-f to force the Flash memory to be entirely copied to the USB disk.
Typing diskman -f is identical to clicking the Flush flash button on
the Disk tools page. It does not remove data from the Flash memory. If
you issue diskman -f and then swap hard disks, the data remaining
in memory will later be written out to the new hard disk, causing some
overlap between it and the old disk.
Whilst the DCM is copying the contents of the Flash memory to disk,
you will be shown a log of its progress. The USB interface can transfer
data at a speed around 100 Kb/s, so large files may take several
minutes to complete.
Once a file has been moved from the Flash memory to disk, any further
data received which would otherwise be appended to that file will
instead be placed in a new file in the Flash memory. Because of this, a
stream may occasionally be fragmented. The automatic options are
chosen to minimize this likelihood by only moving the oldest files, and
by keeping files in Flash memory for a reasonable period of time. If
you choose to transfer files to disk more often than this, more files will
be fragmented.
gfat32 ls : List the files present on the hard disk, with the size of
each file.
gfat32 cpf filename-on-disk destination-filename : Copy
a file from the disk into temporary storage in the Linux filesystem ( e.g.
in your home directory.) Once the file is in the Linux file system, you
can modify or convert it using your own scripts running on the DCM,
or use programs such as scp to transfer it to a remote machine.
gfat32 cpt source-filename filename-on-disk : Copy a file
from the Linux file system onto the disk.
gfat32 mv filename new-filename : Rename a file on the disk.
8.2 Command line tools
The DCM module's Linux operating system can be accessed over a
network via SSH. There are many programs available for your
computer which implement this protocol: ssh is included as part of
most Linux and Unix distributions, whilst for Windows putty is a
reliable free client. ssh is essentially a secure version of programs like
rlogin and telnet, and provides a simple command line interface to
the device. Access to the DCM by SSH is enabled by default, although
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