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# 15  
Old 10-26-2016
I am confused also because my script proposal was for an input file where a number is to be substituted, as you specified in your post#1.
Now it has become a letter.?
# 16  
Old 10-26-2016
Hi guys
sorry for the confusion. Ill explain.

@MadeInGermany:
the solution you provided with pattern/newval works perfectly fine.
I can modify "pattern" to be any portion of the string in each line, and the last digit will be replaced.

THe only change right now is I want to get the "pattern" and "newval" parameters required to do the sed by parsing a third variable, instead of defining them explicitly. The main problem seems to be with evaluating the vars.

Right now if I specify everything on the command line it works:
Code:
pattern='info:200\/text\/name1:1.2.300'

-->(im escaping the / and im definning it in single quotes )
Code:
newval=8

Code:
echo " $pattern "

-> info:200\/text\/name1:1.2.300
Code:
echo " $newval "

--> 8


and call sed:
Code:
sed '/'"$pattern"\.'/ s/\(.*\.\)[0-9]\{1,\}/\1'"$newval"'/' file

input (from file):
Code:
person1_desc: 'info:200/text/name1:1.2.300.X'

output:
Code:
person1_desc: 'info:200/text/name1:1.2.300.8'

This is great. So now I will try to get the values from a new variable called $input_line

Code:
input_line=info:200/text/name1:1.2.300.8

parse it:
Code:
pattern_2=$( echo $input_line | sed 's/\.[^.]*$//' )

--> info:200/text/name1:1.2.300

Code:
newval_2=$( echo  $input_line | sed 's/.*\.//' )

--> 8

Code:
echo " $pattern_2 "

--> info:200/text/name1:1.2.300
Code:
echo "$newval_2 "

--> 8

so now if I call the exact same sed command, it doesnt work:
Code:
sed '/'"$pattern"\.'/ s/\(.*\.\)[0-9]\{1,\}/\1'"$newval"'/' file

I get:
Code:
sed: -e expression #1, char 33: extra characters after command


so thats why I want to
1. escape the slash in $pattern_2
2. not sure if I need to put $pattern_2 in single quotes?
# 17  
Old 10-26-2016
Hi,

I am sorry still it is not clear that what you are trying to achieve .

Quote:
so thats why I want to
1. escape the slash in $pattern_2
2. not sure if I need to put $pattern_2 in single quotes?
See if it helps :
Code:
pattern='info:200/text/name1:1.2.300'
pattern=$(echo $pattern | sed -e 's,/,\\/,g')
echo $pattern
info:200\/text\/name1:1.2.300

# 18  
Old 10-27-2016
I am still a bit confused: when you say .X you seem to mean that X is a number...
The / has no special meaning in an RE (=regular expression). But my sed scripts used the / delimiter. The following is with a different delimiter, #
Code:
sed '\#'"$pattern"\.'# s#\(.*\.\)[0-9]\{1,\}#\1'"$newval"'#' file

Perhaps the following is a little more precise, because it requires the search pattern to be placed left from the replacement area.
Code:
sed 's#\('"$pattern"'.*\.\)[0-9]\{1,\}#\1'"$newval"'#' file

Now you do not need to escape the / in the search pattern (instead need to escape a #).
But you *must* escape the . character! In a RE it matches any character. For example pattern="2.0/text" would find 200/text. But pattern="2\.0/text" only finds 2.0/text.
--
You want to split the string at the last dot. You can use shell-builtins for that
Code:
input_line="info:200/text/name1:1.2.300.8"
pattern_2=${input_line%.*}
echo "$pattern_2"
newval_2=${input_line##*.}
echo "$newval_2"

# 19  
Old 10-31-2016
Code:
sed 's/./3/6;s/./3/16;s/./17/24' sedd1.txt




Moderator's Comments:
Mod Comment Please use CODE tags as required by forum rules!
Last edited by RudiC; 10-31-2016 at 05:28 AM.. Reason: Added CODE tags.
# 20  
Old 10-31-2016
Code:
# cat mytst
Name: 'text1:200/text2:1.2.3.4'
Name2: 'text3:200/text3:1.2.3.17'

Code:
# sed 's/[^:]*.$/whatever'"'"'/g' mytst
Name: 'text1:200/text2:whatever'
Name2: 'text3:200/text3:whatever'

Code:
# sed 's/[^.]*.$/whatever'"'"'/g' mytst
Name: 'text1:200/text2:1.2.3.whatever'
Name2: 'text3:200/text3:1.2.3.whatever'

@Beginner101
Note :
a) sometimes it's easier for people to understand what you need when you provide a well-chosen example of input and output file, rather than long explainations... Smilie
b) the dot before the dollar signe is useless here, but i leave it just to keep in mind that this last char matched (which is here a simple quote), is a little special and need therefore a special threatment.

---------- Post updated at 16:29 ---------- Previous update was at 13:02 ----------

Quote:
Originally Posted by Beginner101
[...]
Code:
sed: -e expression #1, char 33: extra characters after command

so thats why I want to
[...]
Yep this is due to the fact that your pattern contains some / which get parsed.

In order to avoir tedious "escaping escape" gym ... you may want to give a try using ! as reference character in the s!pattern1!pattern2! expression rather than / so that the slash will be taken as litteral.
Last edited by ctsgnb; 10-31-2016 at 12:55 PM..
This User Gave Thanks to ctsgnb For This Post:
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