I have a large log file from which I need to extract file names.
The file looks like this:
/path/to/loremIpsumDolor.sit /more/text/here/notAlways/theSame/here
/path/to/anotherFile.ext /more/text/here/differentText/here
.... about 10 million times
I need to extract the file names like this:
loremIpsumDolor.sit
anotherFile.ext
I figure my first strategy is to find/replace all /path/to/ with ''. But I'm stuck how to remove all characters after the space.
Can you help?
sed 's/ .*//' file
It doesn't take any more. The transformed output appears on standard output, of course.
In theory, you could also use awk to grab the filename from each line as:
awk '{ print $1 }' input_file.log
That, of course, assumes that there are no spaces in any of the filenames. awk defaults to looking for whitespace as the field delimiters, so the above snippet would take the first "field" from your log file (your filename) for each line, and output it.
Pass it to cut:
cut '-d ' -f1 yourfile
a bash-only solution:
while read path otherstuff; do
echo ${path##*/}
done < filename
Related
I have a csv file like the following:
entity_name,data_field_name,type
Unit,id
Track,id,LONG
The second row is missing a comma. I wonder if there might be some regex or awk like tool in order to append commas to the end of line in case there are missing commas in these rows?
Update
I know the requirements are a little vague. There might be several alternative ways to narrow down the requirements such as:
The header row should define the number of columns (and commas) that is valid for the whole file. The script should read the header row first and find out the correct number of columns.
The number of columns might be passed as an argument to the script.
The number of columns can be hardcoded into the script.
I didn't narrow down the requirements at first because I was ok with any of them. Of course, the first alternative is the best but I wasn't sure if this was easy to implement or not.
Thanks for all the great answers and comments. Next time, I will state acceptable alternative requirements explicitly.
You can use this awk command to fill up all rows starting from 2nd row with the empty cell values based on # of columns in the header row, in order to avoid hard-coding # of columns:
awk 'BEGIN{FS=OFS=","} NR==1{nc=NF} NF{$nc=$nc} 1' file
entity_name,data_field_name,type
Unit,id,
Track,id,LONG
Earlier solution:
awk 'BEGIN{FS=OFS=","} NR==1{nc=NF} {printf "%s", $0;
for (i=NF+1; i<=nc; i++) printf "%s", OFS; print ""}' file
I would use sed,
sed 's/^[^,]*,[^,]*$/&,/' file
Example:
$ echo 'Unit,id' | sed 's/^[^,]*,[^,]*$/&,/'
Unit,id,
$ echo 'Unit,id,bar' | sed 's/^[^,]*,[^,]*$/&,/'
Unit,id,bar
Try this:
$ awk -F , 'NF==2{$2=$2","}1' file
Output:
entity_name,data_field_name,type
Unit,id,
Track,id,LONG
With another awk:
awk -F, 'NF==2{$3=""}1' OFS=, yourfile.csv
to present balance to all the awk solutions, following could be a vim only solution
:v/,.*,/norm A,
rationale
/,.*,/ searches for 2 comma's in a line
:v apply a global command on each line NOT matching the search
norm A, enters normal mode and appends a , to the end of the line
This MIGHT be all you need, depending on the info you haven't shared with us in your question:
$ awk -F, '{print $0 (NF<3?FS:"")}' file
entity_name,data_field_name,type
Unit,id,
Track,id,LONG
I have a text file which has some below data:
AB-NJCFNJNVNE-802ac94f09314ee
AB-KJNCFVCNNJNWEJJ-e89ae688336716bb
AB-POJKKVCMMMMMJHHGG-9ae6b707a18eb1d03b83c3
AB-QWERTU-55c3375fb1ee8bcd8c491e24b2
I need to remove the data before the second hyphen (-) and produce another text file with the below output:
802ac94f09314ee
e89ae688336716bb
9ae6b707a18eb1d03b83c3
55c3375fb1ee8bcd8c491e24b2
I am pretty new to linux and trying sed command with unsuccessful attempts for the last couple of hours. How can I get the desired output with sed or any other useful command like awk?
You can use a simple cut call:
$ cat myfile.txt | cut -d"-" -f3- > myoutput.txt
Edit:
Some explanation, as requested in the comments:
cut breaks up a string of text to fields according to a given delimiter.
-d defines the delimiter, - in this case.
-f defines which fields to output. In this case, we want to eliminate everything before the second hyphen, or, in other words, return the third field and onwards (3-).
The rest of the command is just piping the output. cating the file into cut, and then saving the result to an output file.
Or, using sed:
cat myfile.txt | sed -e 's/^.\+-//'
I have a huge .txt file, 300GB to be more precise, and I would like to put all the distinct strings from the first column, that match my pattern into a different .txt file.
awk '{print $1}' file_name | grep -o '/ns/.*' | awk '!seen[$0]++' > test1.txt
This is what I've tried, and as far as I can see it works fine but the problem is that after some time I get the following error:
awk: program limit exceeded: maximum number of fields size=32767
FILENAME="file_name" FNR=117897124 NR=117897124
Any suggestions?
The error message tells you:
line(117897124) has to many fields (>32767).
You'd better check it out:
sed -n '117897124{p;q}' file_name
Use cut to extract 1st column:
cut -d ' ' -f 1 < file_name | ...
Note: You may change ' ' to whatever the field separator is. The default is $'\t'.
The 'number of fields' is the number of 'columns' in the input file, so if one of the lines is really long, then that could potentially cause this error.
I suspect that the awk and grep steps could be combined into one:
sed -n 's/\(^pattern...\).*/\1/p' some_file | awk '!seen[$0]++' > test1.txt
That might evade the awk problem entirely (that sed command substitutes any leading text which matches the pattern, in place of the entire line, and if it matches, prints out the line).
Seems to me that your awk implementation has an upper limit for the number of records it can read in one go of 117,897,124. The limits can vary according to your implementation, and your OS.
Maybe a sane way to approach this problem is to program a custom script that uses split to split the large file into smaller ones, with no more than 100,000,000 records each.
Just in case that you don't want to split the file, then maybe you could look for the limits file correspondent to your awk implementation. Maybe you can define unlimited as the Number of Records value, although I believe that is not a good idea, as you might end up using a lot of resources...
If you have enough free space on disk (because creates a temp .swp file) I suggest to use Vim, vim regex has small difference but you can convert from standard regex to vim regex with this tool http://thewebminer.com/regex-to-vim
The error message says your input file contains too many fields for your awk implementation. Just change the field separator to be the same as the record separator and you'll only have 1 field per line and so avoid that problem, then merge the rest of the commands into one:
awk 'BEGIN{FS=RS} {sub(/[[:space:]].*/,"")} /\/ns\// && !seen[$0]++' file_name
If that's a problem then try:
awk 'BEGIN{FS=RS} {sub(/[[:space:]].*/,"")} /\/ns\//' file_name | sort -u
There may be an even simpler solution but since you haven't posted any sample input and expected output, we're just guessing.
I have a config file like this:
[whatever]
Do I need this? no!
[directive]
This lines I want
Very much text here
So interesting
[otherdirective]
I dont care about this one anymore
Now I want to match the lines in between [directive] and [otherdirective] without matching [directive] or [otherdirective].
Also if [otherdirective] is not found all lines till the end of file should be returned. The [...] might contain any number or letter.
Attempt
I tried this using sed like this:
sed -r '/\[directive\]/,/\[[[:alnum:]+\]/!d
The only problem with this attempt is that the first line is [directive]and the last line is [otherdirective].
I know how to pipe this again to truncate the first and last line but is there a sed solution to this?
You can use the range, as you were trying, and inside it use // negated. When it's empty it reuses last regular expression matched, so it will skip both edge lines:
sed -n '/\[directive\]/,/\[otherdirective\]/ { //! p }' infile
It yields:
This lines I want
Very much text here
So interesting
Here is a nice way with awk to get section of data.
awk -v RS= '/\[directive\]/' file
[directive]
This lines I want
Very much text here
So interesting
When setting RS to nothing RS= it divides the file up in records based on blank line.
So when searching for [directive] it will print that record.
Normally a record is one line, but due to the RS (record selector) is change, it gives the block.
Okay damn after more tries I found the solution or merely one solution:
sed -rn '/\[buildout\]/,/\[[[:alnum:]]+\]/{
/\[[[:alnum:]]+\]/d
p }'
is this what you want?
\[directive\](.*?)\[
Look here
I use the following command on a huge text file
sed 's/\tEN-GB\t//g' "/home/ubuntu/0214/corpus/C.txt"
The file contains a [tab]EN-GB[tab] in each row, but what I get is the original text. I cannot figure out why.
NOTE: when I'm using 's/\t//g' it works and the resulting string is [a lot of no-tabs]EN-GB[a lot of no-tabs] in each row, so the tabs vanished.
UPDATE: Here is the incriminated part of the output from cat -vet:
^#2^#0^#0^#7^#0^#1^#0^#4^#~^#1^#6^#3^#2^#4^#3^#^I^#^I^#0^#^I^#E^#N^#-^#G^#B^#^I^#T^#h^#e^# ^#a^#d^#m^#i^#n^#i^#s^#t^#
I'm out of black magic... thanks in advance
It appears that your sed command is correct but you have some null characters in your text file
Run this sed command to remove nulls first:
sed -i.bak 's/\x0//g; s/\tEN-GB\t//g' "/home/ubuntu/0214/corpus/C.txt"
You can use ANSI-C quoting to represent the TAB character:
sed 's/'$'\tEN-GB\t''//g' filename
EDIT: The output of cat -vet suggests that you have NULL characters in your input. Remove those before piping the results to the above command. Say:
tr -d '\x0' < filename | sed 's/'$'\tEN-GB\t''//g'