Using a string as stdin in linux

Question

I know that we can use a file as stdin like

program << file.txt

but is it possible to use a string as stdin ?

Are you accidentally answering your own question here? That's awesome. — themel
– themel, Commented Nov 16, 2011 at 12:26
@Ernest Friedman-Hill No I was not knowing that :) . I tried like program >> my stinrg but that was not working — Vivek Goel
– Vivek Goel, Commented Nov 16, 2011 at 12:36
The example in your question is invalid. file.txt is not used as input in that case but as the string marking the end of a here doc. — William Pursell
– William Pursell, Commented Nov 16, 2011 at 13:40

Ernest Friedman-Hill · Accepted Answer · 2011-11-16 12:25:27Z

3

You can use syntax called a here document:

program << EOF
input
more input
even more input
EOF

This is supported in several UNIX shells, as well as in some scripting languages like Perl.

answered Nov 16, 2011 at 12:25

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Comments

Didier Trosset · Accepted Answer · 2011-11-16 12:26:20Z

3

Like this:

echo "My string" | program

answered Nov 16, 2011 at 12:26

Didier Trosset

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sorpigal · Accepted Answer · 2011-11-16 12:33:06Z

3

bash supports "here strings" with the following syntax:

program <<<"your input goes here"

This will be treated approximately the same as

echo "your input goes here" > tmp
program < tmp

answered Nov 16, 2011 at 12:33

sorpigal

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