Here document as an argument to bash function

Is it possible to pass a here document as a bash function argument, and in the function have the parameter preserved as a multi-lined variable?

Something along the following lines:

function printArgs {
echo arg1="$1"
echo -n arg2=
cat <<EOF
$2
EOF
}

printArgs 17 <<EOF
18
19
EOF

or maybe:

printArgs 17 $(cat <<EOF
18
19
EOF)

I have a here document that I want to 开发者_Go百科feed to ssh as the commands to execute, and the ssh session is called from a bash function.

The way to that would be possible is:

printArgs 17 "$(cat <<EOF
18
19
EOF
)"

But why would you want to use a heredoc for this? heredoc is treated as a file in the arguments so you have to (ab)use cat to get the contents of the file, why not just do something like:

print Args 17 "18
19"

Please keep in mind that it is better to make a script on the machine you want to ssh to and run that then trying some hack like this because bash will still expand variables and such in your multiline argument.

If you're not using something that will absorb standard input, then you will have to supply something that does it:

$ foo () { while read -r line; do var+=$line; done; }
$ foo <<EOF
a
b
c
EOF

Building on Ned's answer, my solution allows the function to take its input as an argument list or as a heredoc.

printArgs() (
  [[ $# -gt 0 ]] && exec <<< $*
  ssh -T remotehost
)

So you can do this

printArgs uname

or this

printArgs << EOF
uname
uptime
EOF

So you can use the first form for single commands and the long form for multiple commands.

xargs should do exactly what you want. It convert standard input to argument for a command (notice -0 allow to preserve newlines)

$ xargs -0 <<EOF printArgs 17
18
19
EOF

But for you special case, I suggest you to send command on standard input of ssh:

$ ssh host <<EOF
ls
EOF

One way to feed commands to ssh through a here doc and a function is as so:

#!/bin/sh
# define the function
printArgs() {
echo "$1"
ssh -T remotehost
}
# call it with a here document supplying its standard input
printArgs 17 <<EOF
uname
uptime
EOF

The results:

17
Linux remotehost 2.6.32-5-686 ...
Last login: ...
No mail.
Linux
 16:46:50 up 4 days, 17:31,  0 users,  load average: 0.06, 0.04, 0.01