Programming

Hello,
I have a directory structure of seismic files that are stored within about 1000 different directories. The directory structure is typically no more than two levels deep, and they are organized by station name and disc name. Each disc name folder contains a text file called 'vdaq.txt' that I need to convert. Thus, there about a thousand of these vdaq.txt files that I want to import into my C program which converts the file into it's required new binary format.

I can hand-type this command from a command line window:

vdaqconv ~/Documents/Sample_data/SEY08N13/vdaq.txt

and the converter will successfully recognize the file name and directory, do the conversion, and place the converted binary file back into the appropriate directory (in this case, ~/Documents/Sample_data/SEY08N13/).

I can also search for all instances of the file vdaq.txt by using the following command from the top of the directory structure:

find . -name 'vdaq.txt'

The result is a nice long table of all the subdirectories that contain the target file. The information found within the file changes, based on time and station location so I cannot jsut 'blanket copy' over the whole dataset; Each one must be individually converted .

I have tried to pipe the output from the find command into the converter thus:

find . -name 'vdaq.txt' | vdaqconv

However the result is that the converter appears to ignore the output from the find command.

How can I get the converter to process each line from the find command?

I have searched the forums, and probably haven't figured out the appropriate terms to find my answers. Could someone point me in the right direction? - Thanks.

-Daniel

---------- Post updated at 01:07 PM ---------- Previous update was at 11:29 AM ----------

..back from lunch with additional information.
I guess what I was looking for was the question:

How do I use the input from the find command as a series of command-line arguments for a C-code program?"

My sample output from the find command: ( I generated this snippet from the greater subset by using the >> command to output the find results into a sample text file.)
I want to output this data into a program that accepts one command line argument representing the file name that will be converted from text format into binary format.

--Program code snippet:--
So, the question is, how to I interface the two together? I would like to automate the conversion such that the output of the find command continually calls the converter whenever it finds another copy of the vdaq.txt file within the directory structure.

Probably like:

Code:

find . -name 'vdaq.txt' | xargs vdaqconv

Thanks for the tip. However, as written, my C program called vdaqconv is still acting as if there is no argument being passed to it, and it defaults to the default directory and displays useage information. It then blows up with a 'terminated by signal 11' error, as no target file exists in the topmost directory. I *will* however, look into xargs more to see if there is an option that is required. I didn't know about xargs, since I'm still learning unix/linux.

edit--

Okay, I see what is going on with xargs. I used the --verbose switch and this was the output being fed to the converter:
First the input:
Next, the command with the --verbose enabled:
So apparently, the xargs is loading all of the lines into the command line argument separated with white space. Either I need to rework my converter to handle an arbitrary number of command line arguments (up to between one and two thousand), or else come up with an alternative method. Maybe I can use xargs with a temporary file: Dump the find data into a file, open the file, use it for the conversion, then delete the file. Maybe embed it all in a .ksh script or something.

--Gotta go, thanks for your help thus far. It's gotten me unstuck, anyway and thinking about options.

Specify one argument to your script:

Code:

find . -name 'vdaq.txt' | xargs -n 1 vdaqconv

Turk, Thanks a lot! That is the trick. I tested it on the sample directory and in just a flash, the sample files were converted. Now I can proceed with placing some logging information into the program and some error checks, rename the program from its working name to it's official name, then run it on the real thing.

-Dan

Thanks again, this looks like the way to go.