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use sed (preferrably) to replace string in a file

I should edit httpd.conf file with a sh script.
I think the sed would do the job.

The scenario is
1. I have the replace string to put in a variable $NAMING_SPACE, which will be like:
    corbaloc:iiop:www.dot.com:9922/NameService. This value comes (or anything else) as input from user.
2. I need to change the old Corba namespace from the conf file, see below:

<IfModule mod_cbroker.c>
  CbrokerLocation /cbroker
  CbrokerORBArgs -ORBInitRef NameService=corbaloc:iiop:itcmdb.uta.fi:52321/NameService

So I began to think how to do it? Well perhaps if I read the current value from the httpd.conf file and store it to
variable $OLD_NAMING_SPACE. Ok so far. But how?
I am sure that this is not difficult and someone can help me.  

1 Solution
the command is

sed -e "s/oldword/newword/" filename.txt

make sure you escape your slash
you can do that with assuming tcshell I suppose you will know how to convert this to bash

setenv $NAMINGSPACEFIX `echo $NAMING_SPACE | sed -e "s/\//\\\//g;"`

note the quote before the echo and at the end of the command are back ticks not apostrophes.  (usually with the tilde key)

the g makes sure that is picks up more than one file

so the end would look liek

setenv $NAMINGSPACEFIX `echo $NAMING_SPACE | sed -e "s/\//\\\//g;"`
sed -e "s/oldword/$NAMINGSPACEFIX/" filename.txt

this will replace the oldword with the naming space fix
You have to use sed with the "s" and "g" to replace ALL occurrences in a file.  Also, if you use single quotes, you do not have to specity the "-e" flag.

For example:      sed 's/oldword/newword/g' filename.txt
g is actually all the occurances on one line which ensures all occurances in a file.

all the commands are similar to the vi commands for search and replace.

I didn't know about the single quote.  Thanks
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A tip with sed:

sed -e "s/\//\\\//g;"`

You don't HAVE to use the "/" character as a delimiter. You can use any character you like. Use something else and avoid all the escaping, for example using & as the delimiter:

sed -e "s&/&\\/&g"

(you still have to escape the escape)
If you use ampersands you won't have to escape the / in the $NAMING_SPACE variable.  Good call glassd

Also note that single quotes will change all your variables (eg $NAMING_SPACE) to the literal with dollar sign and all.  I did try and my sed allows for double quotes to do the in line action and it seems to work just fine.  I am playing like this

>sed "s&hi&$PATH&;"

/home/willy134/tools/bin:/usr/bin:/usr/local/bin and so on

jm60697Author Commented:
Thank you all, wroking fine now =)


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