rendered paste body~$ sudo strace -etrace=open,close "lpr -P HP_Deskjet_6500_USB_1 -o OptionDuplex=False -o PageSize=Letter -o PageRegion=Letter -o Duplex=None -o InputSlot=Auto -o ColorModel=RGB -o MediaType=Automatic -o OutputMode=Auto -o hpInkSet=Standard"
strace: lpr -P HP_Deskjet_6500_USB_1 -o OptionDuplex=False -o PageSize=Letter -o PageRegion=Letter -o Duplex=None -o InputSlot=Auto -o ColorModel=RGB -o MediaType=Automatic -o OutputMode=Auto -o hpInkSet=Standard:
command not found
~$ which strace
/usr/bin/strace
~$ which lpr
/usr/bin/lpr