Topic:
A quick way to dump a 2D line that is many files into a tape.

Description:
This descibes how to dump a 2D line that is the 27th file on tape.  
It can be done by telling SEG-Y dump to skip 26 tape files, but that takes an
awfully long time.       

Solution:
You can use the unix "mt" command to skip to the file you need to dump, 
and it is much faster than skipping files using the SEG-Y dump command.

In this example, we will call the tape device /dev/rmt/xxx.  
    [Substitute the appropriate tape device name for your workstation]
Note: Be sure to use a "no rewind" tape device. 
      For Sun, your device name will end with an "n", 
      and for SGI, your device name will include "nr".

Here is how you set it up:

1. Put your tape in the drive.  
   In an Xterm, make sure it is rewound, using: mt -f /dev/rmt/xxx rewind.


2. Skip to the 27th file on the tape with the command: mt -f /dev/rmt/xxx fsf 26
   (this command will forward space over 26 EOF marks, and leave you at the
   beginning of the 27th file)
   When the tape reaches the 27th file, the mt command will finish and return
   the prompt in your Xterm.  Now you can proceed to the next step.


3. In IESX => DataManager => Load Seismic => SEGY Dump => 
   a) toggle on "Dump tape", 
   b) specify your tape drive, 
   c) set "Tape rewind" to "No", 
   d) and make sure "Skip tape files" is set to "0".


4. Click on the "Dump..." button, and SEGY dump will dump the 27th file on tape.




Last Modified on: 06-OCT-00