how do I get this
ls -1 | sed 's/\(.*\)/alias \1 "shot \1"/'
into an alias?
Example:
alias asdf "ls -1 | sed 's/\(.*\)/alias \1 "shot \1"/'"
The problem is when I get to the quotes for the alias.
Don't use aliases, use a function:
my_func() {
ls -1 | sed 's/.*/alias & "shot &"/'
}
You should however avoid parsing the output of ls. Please read the link!
In your case, assuming no there is no newlines in the file names, one can use ^0:
my_func() {
printf '%s\n' * | sed 's/\(.*\)/alias \1 "shot \1"/'
}
^0 Which leaves you with the same problems parsing ls would, but without without invoking the extra process, as printf is buildin.
You missed the equal symbol and you must escape double quotes. Try this:
alias asdf="ls -1 | sed 's/\(.*\)/alias \1 \"shot \1\"/'"
Assuming your filenames only contain alphanumerics or DOT or underscore, you should avoid parsing output of ls. Another pitfall is use of pipeline in your command which will create alias only in subshell not in current shell.
You can use this for loop instead:
for f in *; do
alias $f="shot $f"
done
Like this:
alias asdf="ls -1 | sed 's/.*/alias & \"shot &\"/'"
You forgot the assignment operator (=); to get double quotes within double quotes, you have to escape them with \".
Also, I've changed your capture group and backreference to using &, which stands for the complete match.
Notice that programmatically processing the output of ls is not recommended. A robust solution would, for example, use find or fileglobs (like anubhava's answer), but the main point of the question is about escaping double quotes.
Related
How to escape a single quote in a sed expression that is already surrounded by quotes?
For example:
sed 's/ones/one's/' <<< 'ones thing'
Quote sed codes with double quotes:
$ sed "s/ones/one's/"<<<"ones thing"
one's thing
I don't like escaping codes with hundreds of backslashes – hurts my eyes. Usually I do in this way:
$ sed 's/ones/one\x27s/'<<<"ones thing"
one's thing
One trick is to use shell string concatenation of adjacent strings and escape the embedded quote using shell escaping:
sed 's/ones/two'\''s/' <<< 'ones thing'
two's thing
There are 3 strings in the sed expression, which the shell then stitches together:
sed 's/ones/two'
\'
's/'
Escaping single quote in sed: 3 different ways:
From fragile to solid...
Note: This answer is based on GNU sed!!
1. Using double-quotes to enclose sed script:
Simpliest way:
sed "s/ones/one's/" <<< 'ones thing'
But using double-quote lead to shell variables expansion and backslashes to be considered as shell escape before running sed.
1.1. Specific case without space and special chars
In this specific case, you could avoid enclosing at shell level (command line):
sed s/ones/one\'s/ <<<'ones thing'
will work until whole sedscript don't contain spaces, semicolons, special characters and so on... (fragile!)
2. Using octal or hexadecimal representation:
This way is simple and efficient, if not as readable as next one.
sed 's/ones/one\o047s/' <<< 'ones thing'
sed 's/ones/one\x27s/' <<< 'ones thing'
And as following character (s) is not a digit, you coul write octal with only 2 digits:
sed 's/ones/one\o47s/' <<< 'ones thing'
3. Creating a dedicated sed script
cat <<eosedscript >sampleSedWithQuotes.sed
#!$(which sed) -f
s/ones/one's/;
eosedscript
chmod +x sampleSedWithQuotes.sed
From there, you could run:
./sampleSedWithQuotes.sed <<<'ones thing'
one's thing
This is the strongest and simpliest solution as your script is the most readable:$ cat sampleSedWithQuotes.sed
#!/bin/sed -f
s/ones/one's/;
3.1 You coud use -i sed flag:
As this script use sed in shebang, you could use sed flags on command line. For editing file.txt in place, with the -i flag:
echo >file.txt 'ones thing'
./sampleSedWithQuotes.sed -i file.txt
cat file.txt
one's thing
3.2 Mixing quotes AND double quotes
Using dedicated script may simplify mixing quotes and double quotes in same script.
Adding a new operation in our script to enclose the word thing in double quotes:
echo >>sampleSedWithQuotes.sed 's/\bthing\b/"&"/;'
( now our script look like:
#!/bin/sed -f
s/ones/one's/;
s/\bthing\b/"&"/;
)
then
./sampleSedWithQuotes.sed <<<'ones thing'
one's "thing"
The best way is to use $'some string with \' quotes \''
eg:
sed $'s/ones/two\'s/' <<< 'ones thing'
Just use double quotes on the outside of the sed command.
$ sed "s/ones/one's/" <<< 'ones thing'
one's thing
It works with files too.
$ echo 'ones thing' > testfile
$ sed -i "s/ones/one's/" testfile
$ cat testfile
one's thing
If you have single and double quotes inside the string, that's ok too. Just escape the double quotes.
For example, this file contains a string with both single and double quotes. I'll use sed to add a single quote and remove some double quotes.
$ cat testfile
"it's more than ones thing"
$ sed -i "s/\"it's more than ones thing\"/it's more than one's thing/" testfile
$ cat testfile
it's more than one's thing
This is kind of absurd but I couldn't get \' in sed 's/ones/one\'s/' to work. I was looking this up to make a shell script that will automatically add import 'hammerjs'; to my src/main.ts file with Angular.
What I did get to work is this:
apost=\'
sed -i '' '/environments/a\
import '$apost'hammerjs'$apost';' src/main.ts
So for the example above, it would be:
apost=\'
sed 's/ones/one'$apost's/'
I have no idea why \' wouldn't work by itself, but there it is.
Some escapes on AppleMacOSX terminals fail so:
sed 's|ones|one'$(echo -e "\x27")'s|1' <<<'ones thing'
I know this is going to sound like a cop out but I could never get sed working when there were both single and double quotes in the string. To help any newbies like me that are having trouble, one option is to split up the string. I had to replace code in over 100 index.hmtl files. The strings had both single and double quotes so I just split up the string and replaced the first block with
<!-- and the second block with -->. It made a mess of my index.html files but it worked.
use an alternative string seperator like ":" to avoid confusion with different slashes
sed "s:ones:one's:" <<< 'ones thing'
or if you wish to highligh the single quote
sed "s:ones:one\'s:" <<< 'ones thing'
both return
one's thing
I wanted to do grep for keywords with double quotes inside. To give a simple example:
echo "member":"time" | grep -e "member\""
That does not match. How can I fix it?
The problem is that you aren't correctly escaping the input string, try:
echo "\"member\":\"time\"" | grep -e "member\""
Alternatively, you can use unescaped double quotes within single quotes:
echo '"member":"time"' | grep -e 'member"'
It's a matter of preference which you find clearer, although the second approach prevents you from nesting your command within another set of single quotes (e.g. ssh 'cmd').
How can I fix this:
abc="a/b/c"; echo porc | sed -r "s/^/$abc/"
sed: -e expression #1, char 7: unknown option to `s'
The substitution of variable $abc is done correctly, but the problem is that $abc contains slashes, which confuse sed. Can I somehow escape these slashes?
Note that sed(1) allows you to use different characters for your s/// delimiters:
$ abc="a/b/c"
$ echo porc | sed -r "s|^|$abc|"
a/b/cporc
$
Of course, if you go this route, you need to make sure that the delimiters you choose aren't used elsewhere in your input.
The GNU manual for sed states that "The / characters may be uniformly replaced by any other single character within any given s command."
Therefore, just use another character instead of /, for example ::
abc="a/b/c"; echo porc | sed -r "s:^:$abc:"
Do not use a character that can be found in your input. We can use : above, since we know that the input (a/b/c/) doesn't contain :.
Be careful of character-escaping.
If using "", Bash will interpret some characters specially, e.g. ` (used for inline execution), ! (used for accessing Bash history), $ (used for accessing variables).
If using '', Bash will take all characters literally, even $.
The two approaches can be combined, depending on whether you need escaping or not, e.g.:
abc="a/b/c"; echo porc | sed 's!^!'"$abc"'!'
You don't have to use / as pattern and replace separator, as others already told you. I'd go with : as it is rather rarely used in paths (it's a separator in PATH environment variable). Stick to one and use shell built-in string replace features to make it bullet-proof, e.g. ${abc//:/\\:} (which means replace all : occurrences with \: in ${abc}) in case of : being the separator.
$ abc="a/b/c"; echo porc | sed -r "s:^:${abc//:/\\:}:"
a/b/cporc
backslash:
abc='a\/b\/c'
space filling....
As for the escaping part of the question I had the same issue and resolved with a double sed that can possibly be optimized.
escaped_abc=$(echo $abc | sed "s/\//\\\AAA\//g" | sed "s/AAA//g")
The triple A is used because otherwise the forward slash following its escaping backslash is never placed in the output, no matter how many backslashes you put in front of it.
I want to replace IP dynamically but somehwo sed is placing word $IP instead of actual value.
IP=10.50.33.44
PORT=5774
sed -i~ 's/https:\/\/10.11.12.13:8443/https:\/\/$IP:$PORT/g' abc.txt
Can you help me out in getting the correct value?
Use double quotes" for variable expansion:
sed -i~ "s/https:\/\/10.11.12.13:8443/https:\/\/$IP:$PORT/g" abc.txt
and as #Joachim said, use different delimiter. For example,
sed -i~ "s;https://10.11.12.13:8443;https://$IP:$PORT;g" abc.txt
Variation on a theme: I always use single quotes to surround sed/awk/perl... commands as the shell can sometimes trip you up when using double quotes.
I find it best to double quote the variables:
sed -i~ 's/https:\/\/10.11.12.13:8443/https:\/\/'"$IP"':'"$PORT"'/g' abc.txt
As a "belt and braces" and as I usually compose my commands interactively at the command line in bash, the key-binding M-C-e (that's Alt-Control-e on most keyboards) will interpolate the command before it's sent. Letting you visually see what the command is really getting.
If I run these commands from a script:
#my.sh
PWD=bla
sed 's/xxx/'$PWD'/'
...
$ ./my.sh
xxx
bla
it is fine.
But, if I run:
#my.sh
sed 's/xxx/'$PWD'/'
...
$ ./my.sh
$ sed: -e expression #1, char 8: Unknown option to `s'
I read in tutorials that to substitute environment variables from shell you need to stop, and 'out quote' the $varname part so that it is not substituted directly, which is what I did, and which works only if the variable is defined immediately before.
How can I get sed to recognize a $var as an environment variable as it is defined in the shell?
Your two examples look identical, which makes problems hard to diagnose. Potential problems:
You may need double quotes, as in sed 's/xxx/'"$PWD"'/'
$PWD may contain a slash, in which case you need to find a character not contained in $PWD to use as a delimiter.
To nail both issues at once, perhaps
sed 's#xxx#'"$PWD"'#'
In addition to Norman Ramsey's answer, I'd like to add that you can double-quote the entire string (which may make the statement more readable and less error prone).
So if you want to search for 'foo' and replace it with the content of $BAR, you can enclose the sed command in double-quotes.
sed 's/foo/$BAR/g'
sed "s/foo/$BAR/g"
In the first, $BAR will not expand correctly while in the second $BAR will expand correctly.
Another easy alternative:
Since $PWD will usually contain a slash /, use | instead of / for the sed statement:
sed -e "s|xxx|$PWD|"
You can use other characters besides "/" in substitution:
sed "s#$1#$2#g" -i FILE
一. bad way: change delimiter
sed 's/xxx/'"$PWD"'/'
sed 's:xxx:'"$PWD"':'
sed 's#xxx#'"$PWD"'#'
maybe those not the final answer,
you can not known what character will occur in $PWD, / : OR #.
if delimiter char in $PWD, they will break the expression
the good way is replace(escape) the special character in $PWD.
二. good way: escape delimiter
for example:
try to replace URL as $url (has : / in content)
x.com:80/aa/bb/aa.js
in string $tmp
URL
A. use / as delimiter
escape / as \/ in var (before use in sed expression)
## step 1: try escape
echo ${url//\//\\/}
x.com:80\/aa\/bb\/aa.js #escape fine
echo ${url//\//\/}
x.com:80/aa/bb/aa.js #escape not success
echo "${url//\//\/}"
x.com:80\/aa\/bb\/aa.js #escape fine, notice `"`
## step 2: do sed
echo $tmp | sed "s/URL/${url//\//\\/}/"
URL
echo $tmp | sed "s/URL/${url//\//\/}/"
URL
OR
B. use : as delimiter (more readable than /)
escape : as \: in var (before use in sed expression)
## step 1: try escape
echo ${url//:/\:}
x.com:80/aa/bb/aa.js #escape not success
echo "${url//:/\:}"
x.com\:80/aa/bb/aa.js #escape fine, notice `"`
## step 2: do sed
echo $tmp | sed "s:URL:${url//:/\:}:g"
x.com:80/aa/bb/aa.js
With your question edit, I see your problem. Let's say the current directory is /home/yourname ... in this case, your command below:
sed 's/xxx/'$PWD'/'
will be expanded to
sed `s/xxx//home/yourname//
which is not valid. You need to put a \ character in front of each / in your $PWD if you want to do this.
Actually, the simplest thing (in GNU sed, at least) is to use a different separator for the sed substitution (s) command. So, instead of s/pattern/'$mypath'/ being expanded to s/pattern//my/path/, which will of course confuse the s command, use s!pattern!'$mypath'!, which will be expanded to s!pattern!/my/path!. I’ve used the bang (!) character (or use anything you like) which avoids the usual, but-by-no-means-your-only-choice forward slash as the separator.
Dealing with VARIABLES within sed
[root#gislab00207 ldom]# echo domainname: None > /tmp/1.txt
[root#gislab00207 ldom]# cat /tmp/1.txt
domainname: None
[root#gislab00207 ldom]# echo ${DOMAIN_NAME}
dcsw-79-98vm.us.oracle.com
[root#gislab00207 ldom]# cat /tmp/1.txt | sed -e 's/domainname: None/domainname: ${DOMAIN_NAME}/g'
--- Below is the result -- very funny.
domainname: ${DOMAIN_NAME}
--- You need to single quote your variable like this ...
[root#gislab00207 ldom]# cat /tmp/1.txt | sed -e 's/domainname: None/domainname: '${DOMAIN_NAME}'/g'
--- The right result is below
domainname: dcsw-79-98vm.us.oracle.com
VAR=8675309
echo "abcde:jhdfj$jhbsfiy/.hghi$jh:12345:dgve::" |\
sed 's/:[0-9]*:/:'$VAR':/1'
where VAR contains what you want to replace the field with
I had similar problem, I had a list and I have to build a SQL script based on template (that contained #INPUT# as element to replace):
for i in LIST
do
awk "sub(/\#INPUT\#/,\"${i}\");" template.sql >> output
done
If your replacement string may contain other sed control characters, then a two-step substitution (first escaping the replacement string) may be what you want:
PWD='/a\1&b$_' # these are problematic for sed
PWD_ESC=$(printf '%s\n' "$PWD" | sed -e 's/[\/&]/\\&/g')
echo 'xxx' | sed "s/xxx/$PWD_ESC/" # now this works as expected
for me to replace some text against the value of an environment variable in a file with sed works only with quota as the following:
sed -i 's/original_value/'"$MY_ENVIRNONMENT_VARIABLE"'/g' myfile.txt
BUT when the value of MY_ENVIRONMENT_VARIABLE contains a URL (ie https://andreas.gr) then the above was not working.
THEN use different delimiter:
sed -i "s|original_value|$MY_ENVIRNONMENT_VARIABLE|g" myfile.txt