Sed replace ">" to "/>" bash - linux

I'm newbie and I would like to replace "special" caracters with sed. I have an xml file that it is not well formed and at the end of any data row it finish with ">" I need to scrap it and to do it I need to change ">" with "/>". But when I try:
sed -i s/>//>/g FILE
returns => -bash: //: Is a directory
same with:
sed -i s/>/\/>/g FILE
also with
sed -i s,>,\>,g FILE
Man page doesn't solve this problem.
Does anyone face this issue?

You should escape the slash character if you use it a separator:
sed 's/>/\/>/g'
Or use another character e.g.:
sed 's_>_/>_g'
Note that this will replace all matches in the file, not just the last one
If you want to match only > not preceded by /, you can use this:
sed -r 's_[^/]>_/>_g' file

Would sed -i 's/>$//>/g' FILE work for you?
$ echo "<blah> <blah>" | sed 's/>$/\/>/g'
<blah> <blah/>

Related

Sed how to find and replace a value using a bash variable [duplicate]

I have a configuration file (gpsd.default) containing data with the following format:
# If you must specify a non-NMEA driver, uncomment and modify the next line
GPSD_SOCKET="/var/run/gpsd.sock"
GPSD_OPTIONS=""
GPS_DEVICES=""
I am making a change on the file with sed:
sed -i 's/^GPS_DEVICES="".*/GPS_DEVICES="dev/ttyUSB1"/' /etc/default/gpsd.default
or
sed -i '4s/^.*/GPS_DEVICES="dev/ttyUSB1"/' /etc/default/gpsd.default
The above sed command returns error:
sed: bad option in substitution expression
Because the new line contains "/" in its expression.
How to update my sed command to make it work?
This is because you are using a regex containing /, which is the same character sed uses as delimiter.
Just change the sed delimiter to another one, for example ~:
sed -i 's~^GPS_DEVICES="".*~GPS_DEVICES="dev/ttyUSB1"~' /etc/default/gpsd.default
By the way, since you are changing files in /etc, you may want to use -i.bak, so that the original file gets backed up. It is a good practice to prevent loss of important information.
You should update your sed command to this.
sed -i 's/^GPS_DEVICES=\"\".*/GPS_DEVICES=\"dev\/ttyUSB1\"/' /etc/default/gpsd.default

Add many quotation in sed instruction

I have to update line with value containg many quotation characters
sed -i 's/.*sonar.links.issue.*/property "sonar.links.issue", "http://jra.url"'
I get error there. What should i do to do it correctly?
Your replacement string contains slashes "http://", so you shouldn't use / as the delimiter for this sed command, use # as shellter proposes.
To complete its answer, I would add the "g" flag, at the end of the sed expression, to ensure the subsitution is made on the whole line, and not only on the first match with ".sonar.links.issue.".
sed -i 's#.*sonar.links.issue.*#property "sonar.links.issue", "http://jra.url"#g' file
Try
sed -i 's#.*sonar.links.issue.*#property "sonar.links.issue", "http://jra.url"#' file
IHTH

Sed error : bad option in substitution expression

I have a configuration file (gpsd.default) containing data with the following format:
# If you must specify a non-NMEA driver, uncomment and modify the next line
GPSD_SOCKET="/var/run/gpsd.sock"
GPSD_OPTIONS=""
GPS_DEVICES=""
I am making a change on the file with sed:
sed -i 's/^GPS_DEVICES="".*/GPS_DEVICES="dev/ttyUSB1"/' /etc/default/gpsd.default
or
sed -i '4s/^.*/GPS_DEVICES="dev/ttyUSB1"/' /etc/default/gpsd.default
The above sed command returns error:
sed: bad option in substitution expression
Because the new line contains "/" in its expression.
How to update my sed command to make it work?
This is because you are using a regex containing /, which is the same character sed uses as delimiter.
Just change the sed delimiter to another one, for example ~:
sed -i 's~^GPS_DEVICES="".*~GPS_DEVICES="dev/ttyUSB1"~' /etc/default/gpsd.default
By the way, since you are changing files in /etc, you may want to use -i.bak, so that the original file gets backed up. It is a good practice to prevent loss of important information.
You should update your sed command to this.
sed -i 's/^GPS_DEVICES=\"\".*/GPS_DEVICES=\"dev\/ttyUSB1\"/' /etc/default/gpsd.default

I am having trouble with Sed

I am trying to use the sed command to replace this line:
charmm.c36a4.20140107.newcali4.fixhcali.grange.b
with:
charmm.20140911.c36a4.3rd.ghost2.model3rd
When I use:
sed -i '/s/firstline/secondline/g'
It doesn't work. I think the periods are messing it up. How do I get around this?
sed uses regular expressions, so . matches any character. If you want to only match the . character itself, tell sed to look for \.
so to change the first line into the second line:
sed -e 's/charmm\.c36a4.20140107\.newcali4\.fixhcali\.grange\.b/charmm.20140911.c36a4.3rd.ghost2.model3rd/g' < filetochange >newfile
Here, I added "g" so it does it globally, ie, if there are several instances on the same line, all will be changed. If you remove the "g", it will only change the first occurence on each line.
It reads from filetochange and writes to newfile
If you do :
sed -i -e 's/charmm\.c36a4.20140107\.newcali4\.fixhcali\.grange\.b/charmm.20140911.c36a4.3rd.ghost2.model3rd/g' filetochange
it will directly do the change in "filetochange" ... but please be careful, a badly written sed -i could mess up the file and make it unusable
The s command follows this syntax:
s/pattern/replacement/
You need to drop the / in front of the sed command.

Surround all lines in a text file with quotes ('something')

I've got a list of directories that contain spaces.
I need to surround them with ' ' to ensure that my batch scripts will work.
How can one surround each new line with a ' and a ' (quotes).
e.g.
File1:
/home/user/some type of file with spaces
/home/user/another type of file with spaces
To
File2:
'/home/user/some type of file with spaces'
'/home/user/another type of file with spaces'
Use sed?
sed -e "s/\(.*\)/'\1'/"
Or, as commented below, if the directories might contain apostrophes (nightmare if they do) use this alternate
sed -e "s/'/'\\\\''/g;s/\(.*\)/'\1'/"
Using sed:
sed -i "s/^.*$/'&'/g" filename
You can use sed(1) to insert single quotes at the beginning and end of each line in a file as so:
sed -i~ -e "s/^/'/;s/$/'/" the_file
I prefer awk (it's faster than bash and very easy to extend):
awk '{print "\'" $0 "\'"}'
very simple logic, you just need to echo the quotes in front and behind.
while read -r line
do
echo "'$line'"
# do something
done < "file"
Using sd, to surround with ' the command looks like:
sd '(.*)' \''$1'\'
to surround with " the command looks like:
sd '(.*)' '"$1"'
Hopefully you got the idea.

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