This is very very dangerous. The >sandbox.cfg overwrites sandbox.cfg entirely, and doesn't wait for sed to finish reading before it does so! If sed doesn't read in the entire file before the shell truncates it, much or all of it could be lost! That's probably what's happening when you don't use cat. With the cat, it takes a fraction of a second longer, giving sed a chance to read at least some of it (but NOT guaranteed to be all of it).
If you have Linux, you can use sed -i '/expression/' filename to safely edit the file "in place". It creates a temp file, then replaces filename with the temp file.
If you don't, you have to use a temp file yourself:
Last edited by Corona688; 07-01-2011 at 04:27 PM..
I am currently working with a bash script to change some names around in 3 files. I am attempting to do this with sed but I haven't been able to get it so it won't replace partial matches.
Below is an example of the files I am trying to edit.
My main goal is to replace foo with test, but I... (4 Replies)
HI
I have property files having content
QA_server_name=10.232.54.7
QA_port_number=18000
DEV_server_name=10.235.60.73
DEV_port_number=18000
and a .jason file having content like this
{
"server":"localhost"
"port":"17000"
------
}
I will get the parameter... (1 Reply)
Hi,
I have 50 shells in a particular directory. In each shell, we have a variable
MAIL_SUCCESS=abc@xyz.com,def@xyz.com,emi@xyz.com
The variable could be different. Now my requirement is I've to replace abc with def in all the shells present. I have been able to get the command for that:
... (3 Replies)
Hi.
I would like to have experts help on below action.
I have text files in which page nubmers exists in form like
PAGE : 1
PAGE : 2
PAGE : 3 and so on there is other text too. I would like to know is it possible to check the last occurance of Page... (6 Replies)
What command can I use to replace the last part of a text string with different text.
Example: I want to replace the text NAME in the following string with the text NEW_NAME
abc~diff~other~something~NAME
The number of ~ can change. (4 Replies)
I am trying to write a shell script that will allow the typing of a value, then using that value to replace data in a text file.
I suspect I need sed.
The format of the file is:
Variable1:Value1
Variable2:Value2
The interaction would be something like:
Shell Prompt: "Please enter the... (9 Replies)
I have an html file that looks like this (this is just a part of the html file):
<td colspan="3" rowspan="1" style="text-align: center; background-color: rgb(<!-- IDENTIFIER1 -->51, 255, 51);"><small><!-- IDENTIFIER2 -->UP</small></td>
This is to automatically update the status of the... (4 Replies)
I have a file which contains the following data.
Parameters "CParameters"
BEGIN DSSUBRECORD
Name "TgtDB"
Prompt "TgtDB"
Default "edwdev"
ParamType "0"
ParamLength "0"
ParamScale "0"
END DSSUBRECORD
MetaBag... (6 Replies)
I have a text file with following content (3 lines)
filename : output.txt
first line:12/12/2008
second line:12/12/2008
third line:Y
I would like to know how we can replace 'Y' with 'N' in the 3rd line keeping 1st and 2nd lines same as what it was before.
I tried using cat output.txt... (4 Replies)