Question
I requested some data and got a file back that I can't read. What do I do with this file?
Answer
It is first necessary to identify what kind of file this is.
Look for an extension or suffix
Many times, a file will have a suffix on it, like .txt, to indicate the type of file. IRIS will typically send users these kinds of data:
| File suffix | Description |
|---|---|
| .seed, .dataless, .miniseed, .mseed, .dless | Files in SEED format |
| .SAC, .sac | SAC format |
| .SAC_ASCII | SAC ASCII format |
| .tar | This is a tar archive file that probably contains data or many data files. Use the tar command to unwrap them to your disk. |
| .tar.gz | This is a tar archive file that has been gzipped. Use gunzip to decompress the file, followed by the tar command to unwrap the contents. |
| .zip | This is a zip archive file. Use the unzip command to unwrap the contents. |
| .RESP,.resp | An ASCII file containing instrument response information for stations |
Use the file command
Unix systems have a file command that you can run against files. Sometimes the system can identify what kind it is:
% file ms_ascii.tar.gz ms_ascii.tar.gz: gzip compressed data, from Unix
Contact IRIS DMC with a header character dump
Send IRIS DMC a short character dump of the file, since the first few characters in the file can many times reveal the nature of the data. We might be able to tell you what it is and how to access it.
% cat myUnknownFile | od -c | head -50 0000000 0 0 0 0 0 1 V 0 1 0 0 1 1 2 0 0000020 2 . 4 1 5 1 9 9 7 , 1 5 3 , 0 0 0000040 : 0 0 : 0 0 . 0 0 2 0 ~ 1 9 9 7 0000060 , 3 0 5 , 2 3 : 5 9 : 5 9 . 9 9 0000100 7 0 ~ 2 0 1 1 , 0 4 5 , 1 1 : 4 0000120 7 : 0 0 . 0 0 0 0 ~ I R I S _ D 0000140 M C ~
Updated: 05/18/2017
