[Help-bash] Bash syntax for using here-doc's or variables as files in process substitution

[Jesse Hathaway]

I would love to have native bash support for using a variable or a here doc as
file in process substituion, rather than doing something like this:

cat <(cat <<-'EOF'
butter
EOF
)

printf -v bubbles 'bubbles'
cat <(cat <<<"${bubbles}")

[João Eiras]

Maybe...

exec {fd}<<<"long string"
some-command <&$fd
some-command /dev/fd/$fd # < not entirely portable I think
exec {fd}<&-

[Jesse Hathaway]

Thanks, João

Post by João Eiras
exec {fd}<<<"long string"
some-command <&$fd
some-command /dev/fd/$fd # < not entirely portable I think
exec {fd}<&-

that definitely works:

printf -v bubbles 'bubbles'
exec {fd}<<<"${bubbles}"
cat <&$fd
exec {fd}<&-

exec {fd}<<-'EOF'
butter
EOF
cat <&$fd
exec {fd}<&-

I would love something that doesn't requiring managing file
descriptors, but this
is certainly a workable solution.

[João Eiras]

Post by Jesse Hathaway
I would love something that doesn't requiring managing file
descriptors, but this
is certainly a workable solution.

You will always need to pass some sort of file descriptor to your
sub-process, so you can do that implicitly with some process
substitution or explicitly with exec while avoiding an extra process.

[Jesse Hathaway]

Post by João Eiras
You will always need to pass some sort of file descriptor to your
sub-process, so you can do that implicitly with some process
substitution or explicitly with exec while avoiding an extra process.

right, I thought it might be nice to have syntax which allows an
implicit passing, perhaps something like:

cat <(<<<"bubbles")
cat <(<<'EOF'
bubbles
EOF
)

This syntax is apparently supported by zsh in my testing, which I did
not realize
until now.

[João Eiras]

Post by Jesse Hathaway

Post by João Eiras
You will always need to pass some sort of file descriptor to your
sub-process, so you can do that implicitly with some process
substitution or explicitly with exec while avoiding an extra process.

right, I thought it might be nice to have syntax which allows an
cat <(<<<"bubbles")
cat <(<<'EOF'
bubbles
EOF
)

I just tried and the syntax can be collapsed a bit, but again use of
/dev/fd is not that portable.

cat /dev/fd/$fd 0<&- {fd}<<<"asd"