Use shell script to copy a title tag in HTML file-CodePudding

I have two HTML files - a.html and b.html. I would like to replace the title tag in b.html with the one in a.html.

How would we do it using shell script? I know how to do a simple replacement in the same file by using sed command.

a.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document AAAAA</title>
</head>
<body>
    This is Document A
</body>
</html>

b.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document BBBB</title>
</head>
<body>
    This is Document B
</body>
</html>

b.html - afer running the script - Notice "Document BBBBB" is changed to "Document AAAAA"

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document AAAAA</title>
</head>
<body>
    This is Document B
</body>
</html>

CodePudding user response：

GNU sed:

title=`sed -n "s/^.*<title>\(.*\)<\/title>.*$/\1/p" a.html`; \
sed -i "s/^\(.*<title>\).*\(<\/title>.*\)$/\1$title\2/" b.html

BSD/OS X sed:

title=`sed -n "s/^.*<title>\(.*\)<\/title>.*$/\1/p" a.html`; \
sed -i '' "s/^\(.*<title>\).*\(<\/title>.*\)$/\1$title\2/" b.html

Essentially, it takes a.html, replaces the content with its title (\1 group) and sets the result to the title variable.

Then with a very similar regex, it replaces the title in b.html with the variable and saves b.html.

CodePudding user response：

sed -i 's@BBBBB@AAAAA@' b.html

Does that work?