How can I treat the output of a command as a file?

Question

The whiptail command has an option --textbox that has the following description:

--textbox <file> <height> <width>

The first option requires a file as input; I would like to use the output of a command in its place. It seems like this should be possible in bash - possibly with redirection? For the sake of the question, let's say I'd like to view the output of ls -l in a whiptail textbox.

Update

It looks like the marked answer does answer the question I asked, just not as regards to whiptail. For example, cat <(ls -l) works. Hence I will mark the question as answered, even though the specific example of whiptail does not work with process substitution.

I've created [another stackoverflow question](http://stackoverflow.com/q/23089988/118234) to specifically address whiptail, if anyone is interested. — JoBu1324, Apr 15 '14 at 17:00

score 6 · Accepted Answer · answered Apr 15 '14 at 16:29

6

You can use this process substitution syntax:

--textbox <(command) 600 800

Replace command with your custom command.

answered Apr 15 '14 at 16:29

anubhava

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This looks right, and whiptail runs - but it displays an empty textbox for me. Any ideas why? – JoBu1324 Apr 15 '14 at 16:32
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@JoBu1324 Are you sure you are running bash as your shell? – Mark Setchell Apr 15 '14 at 16:38
I just tried it with bash version 4.1.5 and 4.2.45 - same difference. – JoBu1324 Apr 15 '14 at 16:40
Still doesn't work with whiptail, although I'm marking the question as answered (because it is). – JoBu1324 Apr 15 '14 at 16:53
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I think I know why process substitution doesn't work with whiptail's `--textbox` option - the "files" created aren't seekable. `--textbox` allows navigation. – JoBu1324 Apr 15 '14 at 18:05

score -1 · Answer 2 · answered Apr 15 '14 at 16:30

-1

Does this meet your needs? ls -l > my_file whiptail --textbox my_file

answered Apr 15 '14 at 16:30

Freerobots

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Actually, that's what I was specifically trying to avoid! Thanks, though. – JoBu1324 Apr 15 '14 at 16:31
Ha, oh well. Hopefully the other answers are a better fit. – Freerobots Apr 15 '14 at 16:34
This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post. – Rico Apr 15 '14 at 17:22
@Rico, sorry, I think I was overreacting... I'll delete my comment and we can just pretend it never happend ok :) – Freerobots Jul 30 '14 at 21:45

How can I treat the output of a command as a file?

Update

2 Answers2

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