Piping multiple commands


 
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# 1  
Piping multiple commands

Using the below code I want to find all .sff files and extract them. This works but it seems very cheap. Is there a safer more efficient way to go about this?

Code:
#!/bin/bash

G1=(/home/dirone)

find ${G1} -type f -name \*.sff | xargs python /usr/local/bin/sff_extract.py

# 2  
What do you mean by "cheap"? It is standard shell code. Are you trying to bulletproof the code? There is no error checking that I can see.
# 3  
Thanks I just thought it looked as though I could get errors if conditions changed.
# 4  
Quote:
Originally Posted by jrymer
Is there a safer more efficient way to go about this?

Code:
#!/bin/bash

G1=(/home/dirone)

find ${G1} -type f -name \*.sff | xargs python /usr/local/bin/sff_extract.py

If the goal is to treat every conceivable pathname verbatim ...

xargs treats spaces, single quotes, double quotes, and perhaps also underscores specially. If any of those characters occurred in a filename, your xargs solution would misbehave.

There are xargs options to work with logical lines, but those modes of operation sacrifice a great deal of efficiency for an imperfect workaround (quotes would no longer be a problem, but leading/trailing spaces could be).

Some find/xarg implementations support delimiting pathnames with a null byte.

While the following is slightly more efficient since piping isn't required, the primary advantage is robustness: any legal filename, no matter how bizarre, will be passed intact:
Code:
find "${G1}" -type f -name \*.sff -exec python /usr/local/bin/sff_extract.py {} +

Regards,
Alister
 

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