I wanted to print a variable(var="phani") to the end of a text file (2.txt) using sed.
This is my work so far:
$ var="phani";echo sed -e "$a$var" -i 2.txt
But the error i am getting is :
sed: -e expression #1, char 2: extra characters after command
Any suggestions please?
because you're using dbl-quotes (to allow for var expansion), you have to escape the first $ so the shell doesn't try to evaluate '$a', this works for me ..
sed "\$a$(var)" file
I hope this helps.
You need to protect the $a from shell expansion:
var="phani";echo sed -e '$a'"$var" -i 2.txt
Is there a reason that echo "$var" >> 2.txt isn't sufficient? Using sed for this is making an easy task more difficult than it needs to be...
Related
I have abc.sh:
exec $ROOT/Subsystem/xyz.sh
On a Unix box, if I print echo $HOME then I get /HOME/COM/FILE.
I want to replace $ROOT with $HOME using sed.
Expected Output:
exec /HOME/COM/FILE/Subsystem/xyz.sh
I tried, but I'm not getting the expected output:
sed 's/$ROOT/"${HOME}"/g' abc.sh > abc.sh.1
Addition:
If I have abc.sh
exec $ROOT/Subsystem/xyz.sh $ROOT/ystem/xyz1.sh
then with
sed "s|\$INSTALLROOT/|${INSTALLROOT}|" abc.sh
it is only replacing first $ROOT, i.e., output is coming as
exec /HOME/COM/FILE/Subsystem/xyz.sh $ROOT/ystem/xyz1.sh
Say:
sed "s|\$ROOT|${HOME}|" abc.sh
Note:
Use double quotes so that the shell would expand variables.
Use a separator different than / since the replacement contains /
Escape the $ in the pattern since you don't want to expand it.
EDIT: In order to replace all occurrences of $ROOT, say
sed "s|\$ROOT|${HOME}|g" abc.sh
This might work for you:
sed 's|$ROOT|'"${HOME}"'|g' abc.sh > abc.sh.1
This may also can help
input="inputtext"
output="outputtext"
sed "s/$input/${output}/" inputfile > outputfile
The safe for a special chars workaround from https://www.baeldung.com/linux/sed-substitution-variables with improvement for \ char:
#!/bin/bash
to="/foo\\bar#baz"
echo "str %FROM% str" | sed "s#%FROM%#$(echo ${to//\\/\\\\} | sed 's/#/\\#/g')#g"
Using bash, how would one replace all unquoted characters from a file?
I have a system that I can't modify that spits out CSV files such as:
code;prop1;prop2;prop3;prop4;prop5;prop6
0,1000,89,"a1,a2,a3",33,,
1,,,"a55,a10",1,1 L,87
2,25,1001,a4,,"1,5 L",
I need this to become, for a new system being added
code;prop1;prop2;prop3;prop4;prop5;prop6
0;1000;89;a1,a2,a3;33;;
1;;;a55,a10;1;1 L;87
2;25;1001;a4;1,5 L;
If the quotes can be removed after this substitution happens in one command it would be nice :) But I prefer clarity to complicated one-liners for future maintenance.
Thank you
With sed:
sed -e 's/,/;/g' -e ':loop; s/\("\)\([^;]*\);\([^"]*"\)/\1\2,\3/; t loop'
Test:
$ sed -e 's/,/;/g' -e ':loop; s/\("\)\([^;]*\);\([^"]*"\)/\1\2,\3/; t loop' yourfile
code;prop1;prop2;prop3;prop4;prop5;prop6
0;1000;89;"a1,a2,a3";33;;
1;;;"a55,a10";1;1 L;87
2;25;1001;a4;;"1,5 L";
You want to use a csv parser. Parsing csv with shell tools is hard (you will encounter regular expressions soon, and they rarely get all cases).
There is one in almost every language. I recommend python.
You can also do this using excel/openoffice variants by opening the file and then saving with ; as the separator.
You can used sed:
echo '0,1000,89,"a1,a2,a3",33,,' | sed -e "s|\"||g"
This will replace " with the empty string (deletes it), and you can pipe another sed to replace the , with ;:
sed -e "s|,|;|g"
$ echo '0,1000,89,"a1,a2,a3",33,,' | sed -e "s|\"||g" | sed -e "s|,|;|g"
>> 0;1000;89;a1;a2;a3;33;;
Note that you can use any separator you want instead of | inside the sed command. For example, you can rewrite the first sed as:
sed -e "s-\"--g"
I have abc.sh:
exec $ROOT/Subsystem/xyz.sh
On a Unix box, if I print echo $HOME then I get /HOME/COM/FILE.
I want to replace $ROOT with $HOME using sed.
Expected Output:
exec /HOME/COM/FILE/Subsystem/xyz.sh
I tried, but I'm not getting the expected output:
sed 's/$ROOT/"${HOME}"/g' abc.sh > abc.sh.1
Addition:
If I have abc.sh
exec $ROOT/Subsystem/xyz.sh $ROOT/ystem/xyz1.sh
then with
sed "s|\$INSTALLROOT/|${INSTALLROOT}|" abc.sh
it is only replacing first $ROOT, i.e., output is coming as
exec /HOME/COM/FILE/Subsystem/xyz.sh $ROOT/ystem/xyz1.sh
Say:
sed "s|\$ROOT|${HOME}|" abc.sh
Note:
Use double quotes so that the shell would expand variables.
Use a separator different than / since the replacement contains /
Escape the $ in the pattern since you don't want to expand it.
EDIT: In order to replace all occurrences of $ROOT, say
sed "s|\$ROOT|${HOME}|g" abc.sh
This might work for you:
sed 's|$ROOT|'"${HOME}"'|g' abc.sh > abc.sh.1
This may also can help
input="inputtext"
output="outputtext"
sed "s/$input/${output}/" inputfile > outputfile
The safe for a special chars workaround from https://www.baeldung.com/linux/sed-substitution-variables with improvement for \ char:
#!/bin/bash
to="/foo\\bar#baz"
echo "str %FROM% str" | sed "s#%FROM%#$(echo ${to//\\/\\\\} | sed 's/#/\\#/g')#g"
First of all i apologise in case this has been answered before but i couldn't solve my problem.
I need to search a pattern and then replace it with a line of text comprising of both text and variable.Btw i am using bash..
say
$var = "stacko.ver/rulz=" **Note: $var contain double quotes & = & a dot and /**
i want to so the follow
1.Search for ;te.xt = Note: The value to be search contain ; & = and a dot
2.Replace it with
textnum=$var
Of course $var should be replaced with its actual value
My attempts
sed -i "s/;te.xt =/textnum=$var/" file
sed -i "s/;te.xt =/textnum="$var"/" file
sed -i "s/";te.xt ="/"textnum=$var"/" file
None of these actually worked , either sed giving me an error or the value of $var not shown in file
Thanks for the help
Regards
Quoting doesn't help since this is a sed issue, not a bash issue. Just pick a sed s-expression delimiter that doesn't appear in your text:
sed -i "s|;te.xt =|textnum=$var|" file
You can pick any delimiter for s that doesn't appear in your input. sed -e 'streetlight' is a perfectly valid sed command.
I can see the error:
$ var="stacko.ver/rulz="
$ data="foo ;te.xt = bar"
$ sed "s/;te.xt =/textnum=$var/" <<< "$data"
sed: -e expression #1, char 31: unknown option to `s'
The problem is that $var contains a slash, so sed's s/// command is breaking. You need to pick a character that does not appear in $var
$ sed "s#;te.xt =#textnum=$var#" <<< "$data"
foo textnum=stacko.ver/rulz= bar
This can be hard -- what if slash and hash are in $var? Using bash, you can use ANSI-C quoting to use a control character that is unlikely to appear in your data, e.g.
$ sed $'s\037;te.xt =\037textnum=$var\037' <<< "$data"
foo textnum=stacko.ver/rulz= bar
I need to delete the same line in a large number of text files. I have been trying to use sed, but I cannot get it to delete the newline character at the end. The following successfully deletes the line, but not the newline:
sed -i -e 's/VERSION:1//' *.txt
I have tried using the following to delete the newline also, but it does not work:
sed -i -e 's/VERSION:1\n//' *.txt
Is there anyway to specify a newline in a sed substitute command OR is there any other command line tool I can use to achieve my goal? Thank you
You can use the sed command:
sed -i -e '/VERSION:1/d'
for this.
The following transcript gives an example:
pax> echo 'hello
> goodbye
> hello again' | sed '/oo/d'
hello
hello again
You should also check whether you want to match whole lines with, for example:
sed -i -e '/^VERSION:1$/d'
since, as it stands, that will also delete lines like the following:
VERSION:10
CONVERSION:1
sed '/VERSION:1/{:q;N;s/VERSION\n//g;t q}' file