Simple ed questions - insert line with dot

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1

Hi
I've got a trivial question on using ed (yes, I know, other editors are better!)
How do I insert a line that is just a single dot? (That is, how do I insert a line that starts with a dot and then new line)
Thanks
Peter

2

Hi.

What have you tried? ... cheers, drl

3

Here's my entries:

$ ed
a
. enter a line of just a dot
But it doesn't enter a line with a dot, it leaves
insert mode
w file.txt
0 There's nothing in the buffer
q
$

4

Hi.

Here's one way:

#!/usr/bin/env sh

# @(#) s1       Demonstrate one way to get a ".", dot into a file with ed.

set -o nounset
echo

debug=":"
debug="echo"

## Use local command version for the commands in this demonstration.

echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version bash ed

echo

# Create a file.
cat >data1 <<'EOF'
Hi.
Goodbye.
EOF

echo " Input file:"
cat data1

echo
echo " Conversation with ed:"
ed data1 <<'EOF'
1
a
.x
.
s/x//
w
q
EOF

echo
echo " Results from ed"
cat data1

exit 0

Producing:

% ./s1

(Versions displayed with local utility "version")
GNU bash 2.05b.0
GNU ed version 0.2

 Input file:
Hi.
Goodbye.

 Conversation with ed:
13
Hi.
15

 Results from ed
Hi.
.
Goodbye.

cheers, drl

5

Thanks. So I see one way to do it would be to enter a line of:
.x
and then substitute the x for nothing, leaving just the dot.
Thanks for your help
Peter