Hashcat rule help.

[freeroute]

a possible way would be the go through your email list and split it into two files, one with all the unique strings before the @ and one with all unique values after the @ then feed hashcat with something like dictionary1 ?d?d?d?d... @ dictionary2

something along those lines at least

Hi,
Maybe you could help us. (hash's passwords=emails)
We would like to append digits after usernames list, before domains list.

This command works (append 123 after usernames):
"hashcat -m 0 -a 1 hashes.txt -j '$1 $2 $3' usernames.txt domain_names.txt"

But we would like to append all digits between 0-9.
these command not working:
"hashcat -m 0 -a 1 hashes.txt -j '$?d $?d $?d' usernames.txt domain_names.txt" or
"hashcat -m 0 -a 1 hashes.txt -j ?d?d?d usernames.txt domain_names.txt"

Could you help, please?

usernames.txt sample:
eric
tom
angela

domain_names.txt sample:
@aim.com
@ameritech.net
@aol.com

Thanks for your help.