text - bash sed substitution in httpd.conf -

i trying replace line of text in file using sed , bash. here code. think syntaxs may off.

sed -e 's/documentroot /var/www/html/s///usr/share/rt3/html/' /etc/httpd/conf/httpd.conf

when using sed , file paths, it's easier avoid "/" delimiter, else you'll escaping everytime. "picket fence" format makes terrible read.

assuming you're trying replace "documentroot /var/www/html" "documentroot /usr/share/rt3/html/", try this:

sed 's_documentroot /var/www/html_documentroot /usr/share/rt3/html/_' /etc/httpd/conf/httpd.conf 

example:

~> echo "documentroot /var/www/html" | sed 's_documentroot /var/www/html_documentroot /usr/share/rt3/html/_' documentroot /usr/share/rt3/html/ ~> 

edit: comment, you're wanting 1) open file, 2) replace string, , 3) save changes original file. in case, can use sed's -i flag (in-place editing). try this:

sed -i 's_documentroot /var/www/html_documentroot /usr/share/rt3/html/_' /etc/httpd/conf/httpd.conf 

example:

~> echo "documentroot /var/www/html" > file ~> cat file documentroot /var/www/html ~> sed -i 's_documentroot /var/www/html_documentroot /usr/share/rt3/html/_' file ~> cat file documentroot /usr/share/rt3/html/