finding in wrong order so cat is messed up

cfajohnson · 01-15-2015, 09:59 PM

Quote:

Originally Posted by evo2

There's no *need* for printf either. Assuming the OP is using bash, printf is not a shell builtin, a new process is spawned either way. Indeed there are many way to get that output, feel free to post as many of them as you like.

printf is a builtin command in bash, ksh, dash; tr is an external command (many, many times slower).

evo2 · 01-15-2015, 11:31 PM

Hi,

ok, I stand corrected. I know printf is a zsh builtin, but didn't know it was in bash.

Evo2.

jpollard · 01-16-2015, 06:31 AM

Quote:

Originally Posted by evo2

Hi,

If using the sort command from coreutils you can use the -V option to get the desired results without leading zeros.

Evo2.

Missed that one. It should work quite well.

atjurhs · 01-16-2015, 01:30 PM

hi guys,

i didn't create the files or the directories somebody else did, so i can't pad them without running some other commands that i don't know.

what's the difference in these two?

Code:

find . -name '*.dat' -exec cat */*.dat > out.txt

Code:

find . -name '*.dat' -exec cat dir*/*.dat > "$file"

tabby

jpollard · 01-16-2015, 04:31 PM

Both are incorrect - in the same way.

find will locate the file that matches the -name pattern - then the cat will find all files that match the pattern "dir*/*.dat" - for EACH file that matches the -name pattern.

You want to use the file that find found, you replace the "cat dir*/*.dat" with "cat '{}'" which will execute cat only once for each file.

The major problem is that find will use whatever order the files were added to the given directory - and that may not be the order you want them in.

rknichols · 01-16-2015, 05:12 PM

Both are incorrect in that the cat command is completely ignoring whatever find located. All you will get from either one is, "find: missing argument to `-exec'" and an empty output file.