leah@leah-pc:~$ ipcalc 10.0.128.1/18
Address: 10.0.128.1 00001010.00000000.10 000000.00000001
Netmask: 255.255.192.0 = 18 11111111.11111111.11 000000.00000000
Wildcard: 0.0.63.255 00000000.00000000.00 111111.11111111
=>
Network: 10.0.128.0/18 00001010.00000000.10 000000.00000000
HostMin: 10.0.128.1 00001010.00000000.10 000000.00000001
HostMax: 10.0.191.254 00001010.00000000.10 111111.11111110
Broadcast: 10.0.191.255 00001010.00000000.10 111111.11111111
Hosts/Net: 16382 Class A, Private Internet
leah@leah-pc:~$
cat file.txt | tee >(pbcopy) | grep errors
cat file.txt | tee >(pbcopy) >(do_stuff) >(do_more_stuff) | grep errors
man bash