Echo HTML Into Text File

Question

Is there a simple way to echo some HTML code into a text/HTML file?

I'm trying to do:

echo "<!DOCTYPE html>\n<html>\n\t<body>\n\t\t<h1>Hello World!</h1>\n\t</body>\n</html>" > index.html

But get:

-bash: !DOCTYPE: event not found

score 1 · Accepted Answer · answered May 12 '20 at 05:34

1

Use single quote as bash interprets ! as a special char

Also, use -e with echo so that the backslash escapes like \n are interpreted

echo -e '<html>\n<html>\n\t<body>\n\t\t<h1>Hello World!</h1>\n\t</body>\n</html>' > index.html

answered May 12 '20 at 05:34

GMaster

6,322

That depends on how bash was built. In the bash of Solaris 11.4 for instance, \x sequences are expanded by default and echo -e outputs -e (as POSIX currently requires). Use printf instead to get a consistent behaviour. – Stéphane Chazelas May 12 '20 at 06:27
Thanks for the extra tidbit about using -e, which is important since I'm using \n and \t. – GTS Joe May 12 '20 at 07:34

rubaiat · Answer 2 · 2020-05-12T05:25:38.933

0

You can solve this by using single quotes instead of double-quotes. So, this should work as expected -

echo '<!DOCTYPE html>\n<html>\n\t<body>\n\t\t<h1>Hello World!</h1>\n\t</body>\n</html>' > index.html

When you use single quotes, bash doesn’t try to interpret special characters and simply preserves the literal string.

edited May 12 '20 at 05:25

answered May 12 '20 at 04:53

rubaiat

803

score 0 · Answer 3 · answered May 12 '20 at 06:00

You are triggering a history expansion in bash with !. Either turn off history expansions with set +H, use a single quoted string, or use a here-document to write your HTML:

$ cat <<'END_HTML' >index.html
<!DOCTYPE html>
<html>
        <body>
                <h1>Hello World!</h1>
        </body>
</html>
END_HTML

Or, if you want to write out those encoded tabs and newlines as they are:

$ cat <<'END_HTML' >index.html
<!DOCTYPE html>\n<html>\n\t<body>\n\t\t<h1>Hello World!</h1>\n\t</body>\n</html>
END_HTML

History expansions are not triggered within here-documents in bash.

Echo HTML Into Text File

3 Answers3