Question: If I have 10 files called 01-a.txt, 02-a.txt,...10-a.txt - how can I find the files where the number is greater than 5? I would like a general solution, and I would be putting the contents of all files into one file using something like

```
cat *.txt > bigfile.txt

```

I can get files with numbers using

```
ls *[0-9]*

```

but can't seem go beyond that.

thanks.

Answer: 
Assuming the folder contains only these files.

This would list all files where the number is > 5

ls [0-9]\* | awk -F '-' '{if ($1 > 5) print $0}'
```
ls *.txt | perl -n -e '$f = $_; $f =~ s/\D//g; $f > 5 and print'

```