ref: 85ca0c9adc0d507b17f85b6de5227f533d9fb0b6
dir: /rc/bin/uptime/
#!/bin/awk -f BEGIN{ getline sysname < "/dev/sysname"; getline < "/dev/time"; sec = sprintf("%d", $3/$4); ct = sprintf("%02d:%02d:%02d", sec%86400/3600, sec%86400%3600/60, sec%60); printf("%s up %d days, %s\n", sysname, sec/86400, ct); exit }