chraebsli to Programmer [email protected] • 3 months agoTouch a file in Linuxprogramming.devimagemessage-square91fedilinkarrow-up11.17Karrow-down129
arrow-up11.14Karrow-down1imageTouch a file in Linuxprogramming.devchraebsli to Programmer [email protected] • 3 months agomessage-square91fedilink
minus-square@48954246linkEnglish20•edit-23 months agoFeels dangerous to run. What happens if the file already exists and has something important in it? touch -a is probably better
minus-square@gaterushlink9•3 months agoThe other command could just be printf '' >> file to not overwrite it. Or even simpler >>file and then interrupt
minus-square@[email protected]linkfedilink6•3 months ago.“:>>” is “append null” right? Do you get a file with a single ASCII NUL or is it truly empty?
minus-squareTrailblazing Braille Taserlinkfedilink14•3 months agoNot really. I believe : is the “true” builtin. So it’s like running a program that exits with zero and writes nothing to stdout. The >> streams the empty stdout into the named file.
minus-square@[email protected]linkfedilink4•edit-23 months ago$ :|wc -c 0 $ touch /tmp/f; :>>/tmp/f; wc -c /tmp/f 0 /tmp/f
minus-square@[email protected]linkfedilink3•3 months agoYeah! it’s basically a noop, I use it as a placeholder when I’m writing a script, since bash doesn’t accept code blocks with no commands
Feels dangerous to run. What happens if the file already exists and has something important in it?
touch -ais probably betterThe other command could just be
printf '' >> fileto not overwrite it. Or even simpler>>fileand then interruptor
:>>filethen you don’t need to interrupt.“:>>” is “append null” right? Do you get a file with a single ASCII NUL or is it truly empty?
Not really. I believe : is the “true” builtin. So it’s like running a program that exits with zero and writes nothing to stdout. The >> streams the empty stdout into the named file.
$ :|wc -c 0 $ touch /tmp/f; :>>/tmp/f; wc -c /tmp/f 0 /tmp/f
that’s awesome, did not know about that handy operator!
Yeah!
it’s basically a noop, I use it as a placeholder when I’m writing a script, since bash doesn’t accept code blocks with no commands