Appending text in a file

[Steven Elling]

On Friday 25 April 2003 17:05, Jonathan Hutchins wrote:
> Quoting Steven Elling <ellings at kcnet.com>:
> > cat old.ldif | > > sed -e 's/(dn:.*)/1,ou=contacts,dc=tarcanfel,dc=net/' > new.ldif
>
> Excellent!  So that "1" is what does the trick?

You're half right. In your regex, you must have a subexpression; which is 
defined by using a regex between '(' and ')'.  The backreference --- 1 in 
this case --- refers to the text matched by the 1st subexpression.

All the gory details are in the ed(1) manpage.

> s/,mail=.*//

What is your goal here?  Remember, . (dot) refers to any character and with * 
(astriks) following the dot this regex will match 'mail=' followed by zero or 
more characters.  In effect, this substitution will remove everything from 
'mail=' to the end of the line.  If that is your goal, good.

> /modify/d

I haven't seen this before.  I take it you want to match lines containing 
'modify' and then delete the whole line.  Am I right?