I'm trying to do this with sed
sed -i.bak 's,[href="#">bebeco.fr],href="http://www.bebeco.fr,http://mm.eulerian.net/dynclick/bebeco/?eml-publisher=bebeco&eml-name=deme_faible&eemail={email}&eurl=https://www.bebeco.fr/?utm_source=ANIM&utm_medium=Targeting&utm_campaign=deme_faible&utm_term=CCCC_seg_men&utm_content=website">bebeco.fr,g' pour_test_demenagement-lien-faible.html
As you can imagine, due to the multiple meta characters, the sed command line is bugging and not changing the line.
What can I do to solve the problem and not put a \ before each metacharacter?
Do you think awkcan help, without going into programming?
TIA
You are falling into the trap of thinking sed can operate on strings. It cannot. It operates on regexps with additional "special" characters. Just use awk as it does support string operations. Here's how to replace an old string with a new string:
awk -v old="original" -v new="replacement" 's=index($0,old){$0=substr($0,1,s-1) new substr($0,s+length(old))}1' file
It would be great if sed had a way to support strings like grep does with -F but it doesn't. It'd also be great if there was a briefer way to write it in awk but there isn't. So let's just suck it up and do string operations as provided by the tool that supports them instead of trying to find "special" characters that will sometimes work as delimiters and cobble together escape sequences to try to disable regexp metacharacters.
I would simply use a different separator. What about good old ~? The data as shown does not contain the ~:
sed 's~SEARCH~REPLACE~'
Do you think awk can help, without going into programming?
:) Since awk is a programming language, I don't think it is possible without going into programming. However, I think sed is ok for that job.
Your regex syntax is hosed. [href="#">bebeco.fr] matches a single character which is one of h, r, e, etc. On top of that, you have three fields where sed only permits two, so it's not clear what you are trying to accomplish; but perhaps something like
sed -i.bak 's,href="#">bebeco.fr,href="http://mm.eulerian.net/dynclick/bebeco/?eml-publisher=bebeco\&eml-name=deme_faible\&eemail={email}\&eurl=https://www.bebeco.fr/?utm_source=ANIM\&utm_medium=Targeting\&utm_campaign=deme_faible\&utm_term=CCCC_seg_men\&utm_content=website">bebeco.fr,g' pour_test_demenagement-lien-faible.html
That is, replace the hash in the double-quoted string in href="#">bebeco.fr with a long URL.
You can try to create and escaped pattern
MyStringSearch='ref="#">bebeco.fr'
MyStringSearchEsc="$( printf '%s' "${MyStringSearch}" | sed 's#\[]["\&*.\\/+?]#\\&#g' )"
MyStringReplace='href="http://mm.eulerian.net/dynclick/bebeco/?eml-publisher=bebeco\&eml-name=deme_faible\&eemail={email}\&eurl=https://www.bebeco.fr/?utm_source=ANIM\&utm_medium=Targeting\&utm_campaign=deme_faible\&utm_term=CCCC_seg_men\&utm_content=website">bebeco.fr'
MyStringReplaceEsc="$( printf '%s' "${MyStringReplace}" | sed 's#\[\\/\&"]#\\&#g' )"
before us it in final sed.
sed "s/${MyStringSearchEsc}/${MyStringReplaceEsc}/g" pour_test_demenagement-lien-faible.html
Related
how to tell awk ignore the delmiter in double quotation marks
eg
line='test,t2,t3,"t5,"'
$(echo $line | awk -F "," '{print $4}')
Expected value is "t5,"
but in fact is "t5"
how to get "t5,"?
With GNU awk for FPAT, all you need for your case is:
$ line='test,t2,t3,"t5,"'
$ echo "$line" | awk -v FPAT='([^,]*)|("[^"]*")' '{print $4}'
"t5,"
and if your awk can contain newlines and escaped quotes then see What's the most robust way to efficiently parse CSV using awk?.
Your arbitrary input could be checked or if you know where your input is not well formatted, use substr() starting from index 2 in column 4.
$ echo 'test,t2,t3,"t5,"' | awk -F, '{printf "%s,\n", substr($4,2) }'
t5,
Perhaps this is better.
echo 'test,t2,t3,"t5,"' | awk -F, '{print $(NF-1),$NF}' OFS=,
"t5,"
In the general case, you can't. You need a full parser to remember a tag, change state, then go back to the prior state when it encounters the matching tag. You can't do it with a regular expression unless you make a lot of assumptions about the shape of your data--and since I see you're parsing CSV, those assumptions will not hold true.
If you like awk, I suggest trying perl for this problem. You can either use somebody else's CSV parsing library (search here), or you can write your own. Of course, there's no reason you can't write a CSV parser in pure awk, so long as you understand that this is not what awk is good at. You need to parse character by character (don't separate records by newlines), remember the current state (is the line quoted?) and remember the previous character to see whether it was a backslash (for treating a quote as a literal quote or a comma as a literal comma). You need to remember the previous quote so you can parse "" as an escaped quote instead of a malformed field. It's kind of fun, and it's a bitch. Use somebody else's library if you like. I wouldn't choose awk to write any parser where the records don't have an obvious separator.
Edit: Ed Morton actually did write a full CSV parser for Gawk, which he linked to in his answer. I helped him break it, and he quickly fixed the problem case. His script will be useful, though it will be somewhat unwieldy to adapt to real-world uses.
Problem - I have a set of strings that essentially look like this:
|AAAAAA|BBBBBB|CCCCCCC|...|XXXXXXXXX|...|ZZZZZZZZZ|
The '...' denotes omitted fields.
Please note that the fields between the pipes ('|') can appear in ANY ORDER and not all fields are necessarily present. My task is to find the "XXXXXXX" field and extract it from the string; I can specify that field with a regex and find it with grep/awk/etc., but once I have that one line extracted from the file, I am at a loss as to how to extract just that text between the pipes.
My searches have turned up splitting the line into individual fields and then extracting the Nth field, however, I do not know what N is, that is the trick.
I've thought of splitting the string by the delimiter, substituting the delimiter with a newline, piping those lines into a grep for the field, but that involves running another program and this will be run on a production server through near-TB of data, so I wanted to minimize program invocations. And I cannot copy the files to another machine nor do I have the benefit of languages like Python, Perl, etc., I'm stuck with the "standard" UNIX commands on SunOS. I think I'm being punished.
Thanks
As an example, let's extract the field that matches MyField:
Using sed
$ s='|AAAAAA|BBBBBB|CCCCCCC|...|XXXXXXXXX|12MyField34|ZZZZZZZZZ|'
$ sed -E 's/.*[|]([^|]*MyField[^|]*)[|].*/\1/' <<<"$s"
12MyField34
Using awk
$ awk -F\| -v re="MyField" '{for (i=1;i<=NF;i++) if ($i~re) print $i}' <<<"$s"
12MyField34
Using grep -P
$ grep -Po '(?<=\|)[^|]*MyField[^|]*' <<<"$s"
12MyField34
The -P option requires GNU grep.
$ sed -e 's/^.*|\(XXXXXXXXX\)|.*$/\1/'
Naturally, this only makes sense if XXXXXXXXX is a regular expression.
This should be really fast if used something like:
$ grep '|XXXXXXXXX|' somefile | sed -e ...
One hackish way -
sed 's/^.*|\(<whatever your regex is>\)|.*$/\1/'
but that might be too slow for your production server since it may involve a fair amount of regex backtracking.
I have a command whose output is of the form:
[{"foo1":<some value>,"foo2":<some value>,"foo3":<some value>}]
I want to take the output of this command and just get the value corresponding to foo2
How do I use sed/awk or any other shell utility readily available in a bash script to do this?
Assuming that the values do not contain commas, this sed rune will do it:
sed -n 's/.*"foo2":\([^,]*\),.*/\1/'p
sed -n tells sed not to print lines by default.
The s ("substitute") command uses a regexp group delimited by \( and \) to pick out just the bit you want.
"foo2": provides the context needed to find the right value.
[^,]* means "a character that is not a comma, any number of times". This is your . If values are not delimited by commas, change this (and the comma after the grouping parens) to match correctly.
.* means "any character, any number of times", and it is used to match all the characters before and after the bit you want. Now the regexp will match the entire line.
\1 means the contents of the grouping parentheses. sed will substitute the string that matches the pattern (which is the whole line, because we used .* at the beginning and end) with the contents of the parens, .
Finally, the p on the end means "print the resulting line".
With this awk for example:
$ awk -F[:,] '{print $4}' file
<some value2>
-F[:,] sets possible field separators as : or ,. Then, it is a matter of counting the position in which <some value> of foo2 are. It happens to be the 4th.
With sed:
$ sed 's/.*"foo2":\([^,]*\).*/\1/g' file
<some value2>
.*"foo2":\([^,]*\).* gets the string coming after foo2: and until the comma appears. Then it prints it back with \1.
Your block of data looks like JSON. There is no native JSON parsing in bash, sed or awk, so ALL the answers here will either suggest that you use a different, more appropriate tool, or they will be hackish and might easily fail if your real data looks different from the example you've provided here.
That said, if you are confident that your variable:value blocks and line structure are always in the same format as this example, you may be able to get away with writing your own (very) basic parser that will work for just your use case.
Note that you can't really parse things in sed, it's just not designed for that. If your data always looks the same, a sed solution may be sufficient ... but remember that you are simply pattern matching, not parsing the input data. There are other answers already which cover this.
For very simple matching of the string that appears after the colon after "foo2", as Peter suggested, you could use the following:
$ data='[{"foo1":11,"foo2":222,"foo3":3333}]'
$ echo "$data" | sed -ne 's/.*"foo2":\([^,]*\),.*/\1/p'
As I say, this should in no way be confused with parsing of your JSON. It would work equally well (or badly) with an input string of abcde"foo2":bar,abcde.
In awk, you can make things that are a bit more advanced, but you still have serious limitations when it comes to JSON. For example, if you choose to separate fields with commas, but then you put a comma inside the <some value> in your data, awk doesn't know how to distinguish it from a field separator.
That said, if your JSON is only one level deep (i.e. matches your sample data), the following might work for you:
$ data='[{"foo1":11,"foo2":222,"foo3":3333}]'
$ echo "$data" | awk -F: -vRS=, '{gsub(/[^[:alnum:]]/,"",$1)} $1=="foo2" {print $2}'
This awk script considers commas as record separators and colons as field separators. It does not support any level of depth in your JSON, and depends on alphanumeric variable names. But it should handle JSON split on to multiple lines.
Alternately, if you want to avoid ugly hacks, and perl or python solutions don't work for you, you might want to try out jsawk. With it, you might use something like this:
$ data='[{"foo1":11,"foo2":222,"foo3":3333}]'
$ echo "$data" | jsawk -a 'return this.foo2'
[222]
SEE ALSO: Parsing json with awk/sed in bash to get key value pair
This worked for me. You can Try this one
echo "[{"foo1":<some value>,"foo2":<some value>,"foo3":<some value>}]" | awk -F"[:,]+" '{ if($3=="foo2") { print $4 }}'
Above line awk uses multiple field separators.I have used colon and comma here
Since this looks like JSON, let's parse it like JSON:
perl -MJSON -ne '$json = decode_json($_); print $json->[0]{foo2}, "\n"' <<END
[{"foo1":"some value","foo2":"some, value","foo3":"some value"}]
END
some, value
For some reason I can't seem to find a straightforward answer to this and I'm on a bit of a time crunch at the moment. How would I go about inserting a choice line of text after the first line matching a specific string using the sed command. I have ...
CLIENTSCRIPT="foo"
CLIENTFILE="bar"
And I want insert a line after the CLIENTSCRIPT= line resulting in ...
CLIENTSCRIPT="foo"
CLIENTSCRIPT2="hello"
CLIENTFILE="bar"
Try doing this using GNU sed:
sed '/CLIENTSCRIPT="foo"/a CLIENTSCRIPT2="hello"' file
if you want to substitute in-place, use
sed -i '/CLIENTSCRIPT="foo"/a CLIENTSCRIPT2="hello"' file
Output
CLIENTSCRIPT="foo"
CLIENTSCRIPT2="hello"
CLIENTFILE="bar"
Doc
see sed doc and search \a (append)
Note the standard sed syntax (as in POSIX, so supported by all conforming sed implementations around (GNU, OS/X, BSD, Solaris...)):
sed '/CLIENTSCRIPT=/a\
CLIENTSCRIPT2="hello"' file
Or on one line:
sed -e '/CLIENTSCRIPT=/a\' -e 'CLIENTSCRIPT2="hello"' file
(-expressions (and the contents of -files) are joined with newlines to make up the sed script sed interprets).
The -i option for in-place editing is also a GNU extension, some other implementations (like FreeBSD's) support -i '' for that.
Alternatively, for portability, you can use perl instead:
perl -pi -e '$_ .= qq(CLIENTSCRIPT2="hello"\n) if /CLIENTSCRIPT=/' file
Or you could use ed or ex:
printf '%s\n' /CLIENTSCRIPT=/a 'CLIENTSCRIPT2="hello"' . w q | ex -s file
Sed command that works on MacOS (at least, OS 10) and Unix alike (ie. doesn't require gnu sed like Gilles' (currently accepted) one does):
sed -e '/CLIENTSCRIPT="foo"/a\'$'\n''CLIENTSCRIPT2="hello"' file
This works in bash and maybe other shells too that know the $'\n' evaluation quote style. Everything can be on one line and work in
older/POSIX sed commands. If there might be multiple lines matching the CLIENTSCRIPT="foo" (or your equivalent) and you wish to only add the extra line the first time, you can rework it as follows:
sed -e '/^ *CLIENTSCRIPT="foo"/b ins' -e b -e ':ins' -e 'a\'$'\n''CLIENTSCRIPT2="hello"' -e ': done' -e 'n;b done' file
(this creates a loop after the line insertion code that just cycles through the rest of the file, never getting back to the first sed command again).
You might notice I added a '^ *' to the matching pattern in case that line shows up in a comment, say, or is indented. Its not 100% perfect but covers some other situations likely to be common. Adjust as required...
These two solutions also get round the problem (for the generic solution to adding a line) that if your new inserted line contains unescaped backslashes or ampersands they will be interpreted by sed and likely not come out the same, just like the \n is - eg. \0 would be the first line matched. Especially handy if you're adding a line that comes from a variable where you'd otherwise have to escape everything first using ${var//} before, or another sed statement etc.
This solution is a little less messy in scripts (that quoting and \n is not easy to read though), when you don't want to put the replacement text for the a command at the start of a line if say, in a function with indented lines. I've taken advantage that $'\n' is evaluated to a newline by the shell, its not in regular '\n' single-quoted values.
Its getting long enough though that I think perl/even awk might win due to being more readable.
A POSIX compliant one using the s command:
sed '/CLIENTSCRIPT="foo"/s/.*/&\
CLIENTSCRIPT2="hello"/' file
Maybe a bit late to post an answer for this, but I found some of the above solutions a bit cumbersome.
I tried simple string replacement in sed and it worked:
sed 's/CLIENTSCRIPT="foo"/&\nCLIENTSCRIPT2="hello"/' file
& sign reflects the matched string, and then you add \n and the new line.
As mentioned, if you want to do it in-place:
sed -i 's/CLIENTSCRIPT="foo"/&\nCLIENTSCRIPT2="hello"/' file
Another thing. You can match using an expression:
sed -i 's/CLIENTSCRIPT=.*/&\nCLIENTSCRIPT2="hello"/' file
Hope this helps someone
The awk variant :
awk '1;/CLIENTSCRIPT=/{print "CLIENTSCRIPT2=\"hello\""}' file
I had a similar task, and was not able to get the above perl solution to work.
Here is my solution:
perl -i -pe "BEGIN{undef $/;} s/^\[mysqld\]$/[mysqld]\n\ncollation-server = utf8_unicode_ci\n/sgm" /etc/mysql/my.cnf
Explanation:
Uses a regular expression to search for a line in my /etc/mysql/my.cnf file that contained only [mysqld] and replaced it with
[mysqld]
collation-server = utf8_unicode_ci
effectively adding the collation-server = utf8_unicode_ci line after the line containing [mysqld].
I had to do this recently as well for both Mac and Linux OS's and after browsing through many posts and trying many things out, in my particular opinion I never got to where I wanted to which is: a simple enough to understand solution using well known and standard commands with simple patterns, one liner, portable, expandable to add in more constraints. Then I tried to looked at it with a different perspective, that's when I realized i could do without the "one liner" option if a "2-liner" met the rest of my criteria. At the end I came up with this solution I like that works in both Ubuntu and Mac which i wanted to share with everyone:
insertLine=$(( $(grep -n "foo" sample.txt | cut -f1 -d: | head -1) + 1 ))
sed -i -e "$insertLine"' i\'$'\n''bar'$'\n' sample.txt
In first command, grep looks for line numbers containing "foo", cut/head selects 1st occurrence, and the arithmetic op increments that first occurrence line number by 1 since I want to insert after the occurrence.
In second command, it's an in-place file edit, "i" for inserting: an ansi-c quoting new line, "bar", then another new line. The result is adding a new line containing "bar" after the "foo" line. Each of these 2 commands can be expanded to more complex operations and matching.
I've been searching google for ever, and I cannot find an example of how to do this. I also do not grasp the concept of how to construct a regular expression for SED, so I was hoping someone could explain this to me.
I'm running a bash script against a file full of lines of text that look like this: 2222,H,73.82,04,07,2012
and I need to make them all look like this: 2222,H,73.82,04072012
I need to remove the last two commas, which are the 16th and 19th characters in the line.
Can someone tell me how to do that? I was going to use colrm, which is blessedly simple, but i can't seem to get that installed in CYGWIN. Please and thank you!
I'd use awk for this:
awk -F',' -v OFS=',' '{ print $1, $2, $3, $4$5$6 }' inputfile
This takes a CSV file and prints the first, second and third fields, each followed by the output field separator (",") and then the fourth, fifth and sixth fields concatenated.
Personally I find this easier to read and maintain than regular expression-based solutions in sed and it will cope well if any of your columns get wider (or narrower!).
This will work on any string and will remove only the last 2 commas:
sed -e 's/\(.*\),\([^,]*\),\([^,]*\)$/\1\2\3/' infile.txt
Note that in my sed variant I have to escape parenthesis, YMMV.
I also do not grasp the concept of how to construct a regular
expression for SED, so I was hoping someone could explain this to me.
The basic notation that people are telling you here is: s/PATTERN/REPLACEMENT/
Your PATTERN is a regular expression, which may contain parts that are in brackets. Those parts can then be referred to in the REPLACEMENT part of the command. For example:
> echo "aabbcc" | sed 's/\(..\)\(..\)\(..\)/\2\3\1/'
bbccaa
Note that in the version of sed I'm using defaults to the "basic" RE dialect, where the brackets in expressions need to be escaped. You can do the same thing in the "extended" dialect:
> echo "aabbcc" | sed -E 's/(..)(..)(..)/\2\3\1/'
bbccaa
(In GNU sed (which you'd find in Linux), you can get the same results with the -r options instead of -E. I'm using OS X.)
I should say that for your task, I would definitely follow Johnsyweb's advice and use awk instead of sed. Much easier to understand. :)
It should work :
sed -e 's~,~~4g' file.txt
remove 4th and next commas
echo "2222,H,73.82,04,07,2012" | sed -r 's/(.{15}).(..)./\1\2/'
Take 15 chars, drop one, take 2, drop one.
sed -e 's/(..),(..),(....)$/\1\2\3/' myfile.txt