Division through zero

[yvesh]

If you don't have any swap / your swap is zero byte you get an division by zero error ($2)

free -b | awk '$ 1 == "Swap:" {total=$ 2; used=$ 3; free=$ 4; pfree=($ 4*100/$ 2); pused=($ 3*100/$ 2); if("$1" == "") {printf("%.0f", free )} else {printf("%.0f", $1 "" )} }'

awk: cmd. line:1: (FILENAME=- FNR=3) fatal: division by zero attempted

free -h
              total        used        free      shared  buff/cache   available
Mem:            ....
Swap:            0B          0B          0B

[skblnx]

A bit late now, but might be helpful for someone else:
Quickfix: Use mawk if your machine has it. All my systems with mawk (mainly Debian Buster & Bullseye) execute this command fine, only the ones with GNU awk fail with the division by zero error.

[pocheoleg]

free -b | awk '$ 1 == "Swap:" {total=$ 2; used=$ 3; free=$ 4; if($ 2 == 0) {pfree=0; pused=0} else {pfree=($ 4*100/$ 2); pused=($ 3*100/$ 2)}; if("$1" == "") {printf("%.0f", free )} else {printf("%.0f", $1 "" )} }'