Re^3: how perl do 'envsubst'

Yep, you can see it in action with

$ echo <(echo foo)
/dev/fd/63
[download]

But, now I just realized there is still a mystery!

$ ls /dev/fd
0  1  2  3
[download]

So... how can a program open /dev/fd/63 if it doesn't exist?

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Re^4: how perl do 'envsubst' by jo37 (Curate) on Jul 03, 2024 at 19:55 UTC
So... how can a program open /dev/fd/63 if it doesn't exist? Because it does exist at the time the command is run: `$ echo <(echo foo) $(ls /dev/fd) /dev/fd/63 0 1 2 3 63` [download] Greetings, 🐻 `$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$`	[reply] [d/l]
Re^5: how perl do 'envsubst' by NERDVANA (Priest) on Jul 03, 2024 at 20:55 UTC
Ah-ha! I forgot /dev/fd was a symlink to /proc/self/fd.	[reply]
Re^4: how perl do 'envsubst' by vincentaxhe (Scribe) on Jul 04, 2024 at 05:58 UTC
if run kmonad <(echo $config), could bind to /dev/fd/61; but use perl only /dev/fd/0 is guaranteed to exist, cann't change to others;	[reply]