sorting ls-l owners in Unix - unix

I want to sort the owners in alphabetical order from a call to ls -l and cannot figure out a way to do it. I know something like ls-l | sort would sort the file name but how do i sort the owners in order?

The owner is the third field, so use -k 3:
ls -l | sort -k 3
You can extend this idea to sorting based on other fields, and you can have multiple -k options. For instance, maybe you want to sort by owner, and then size in descending order:
ls -l | sort -k 3,3 -k 5rn

I am not sure if you want only the owners or the whole information sorted by owner. In the former case superfo's solution is almost correct.
Additionally you need to remove repeating white spaces from ls's output with tr because otherwise cut that uses them as a delimiter won't work in all directories.*
So in the end you get this:
ls -l | tr -s ' ' | cut -d ' ' -f 3 | sort | uniq
*Some directories have a two digit value in the second field and all other lines with a single digit get an additional whitespace to preserve the layout.

How about ...
ls -l | cut -d ' ' -f 3 | sort | uniq

Try this:
ls -l | awk '{print $3, $4, $8}' | sort
It will print the user name, the group name and the file name. (File name cannot contain spaces)
ls -l | awk '{print $3, $4, $0}' | sort
This will print the user name, group name and the full ls -l output, sorted by the user name first, then the group name, then what ls -l prints first

Related

Get a list of unique sender(from=) domains in postfix maillog

I am currenlty trying to extract all the sender domains from maillog. I am able to do some of that with the below command but the output is not quite what I desired. What would be the best approach to retrieve a unique list of sender domain from maillog?
grep from= /var/log/maillog | awk '{print $7}' | sort | uniq -c | sort -n
output
1 from=<user#test.com>,
1 from=<apache#app1.com>,
2 from=<bounceld_5BFa-bx0p-P3tQ-67Nn#example.com>,
2 from=<bounceld_19iI-HqaS-usVU-fqe5#example.com>,
12 reject:
666 from=<>,
desired output
test.com
app1.com
example.com
See useless use of grep; if you are using Awk anyway, you don't really need grep at all.
awk '$7 ~ /from=.*#/{split($7, a, /#/); ++count[a[2]] }
END { for(dom in count) print count[dom], dom }' /var/log/maillog
Collecting the counts in an associative array does away with the need to call sort and uniq, too. Obviously, if you don't care about the count, don't print count[dom] at the end.
This should give you the answer:
grep from= /var/log/maillog | awk '{print $7}' | grep -Po '(?=#).{1}\K.*(?=>)' | sort -n | uniq -c
... change last items to "| sort | uniq" to remove the counts.
References:
https://www.baeldung.com/linux/bash-remove-first-characters {1}\K use
Extract email addresses from log with grep or sed -Po grep function

Can someone explain me the unix command the following command

I want to validate the file. As per validation, I need to check the length of each column, null or not null and primary constant of that file.
cat File_name| awk -F '|' '{print NF}' | sort | uniq
This command split lines of the file on tokens using pipe | as delimiter, print number of tokens on each row (NF variable), sort the output (sort command) and on the end get only uniq numbers (uniq command).
The script can be optimised getting rid of cat command and combine it in awk and use parameter of sort to get uniq records:
awk -F '|' '{print NF}' file_name | sort -u

grep multiple files get count of unique cut

I think I'm close on this, and saw similar questions but couldn't get it to work as I want. So, I have several log files and I would like to count the occurrences of several different service calls by date.
First I tried the below, the cut is just to get the first element (date) and 11th element (name of service call), which is specific to my log file:
grep -E "invoking webservice" *.log* | cut -d ' ' -f1 -f11 | sort | uniq -c
But this returned something that looks like:
5 log_1.log:2017-12-05 getLegs()
10 log_1.log:2017-12-05 getArms()
7 log_2.log:2017-12-05 getLegs()
13 log_2.log:2017-12-04 getLegs()
What I really want is:
12 2017-12-05 getLegs()
10 2017-12-05 getArms()
13 2017-12-04 getLegs()
I've seen examples where they cat * first, but looks like the same problem.
cat * | grep -E "invoking webservice" *.log* | cut -d ' ' -f1 -f11 | sort | uniq -c
What am I doing wrong? As always, thanks a lot!
Your issue seems to be that grep prefixes the matched lines with the filenames. (grep has this behavior when multiple filenames are specified, to disambiguate the results.) You can pass the -h to grep to not print the filenames:
grep -h "invoking webservice" *.log | cut -d ' ' -f1 -f11 | sort | uniq -c
Note that I dropped the -E flag, because it is used to enable extended regex support, and your example doesn't need it.
Alternatively, you could use cat to dump the content of files to standard output, and pipe that to grep. That would work, because it removes the need for filename parameters for grep:
cat *.log | grep "invoking webservice" | cut -d ' ' -f1 -f11 | sort | uniq -c

sort and uniq oneliner

Is there a oneliner for for sort and uniq given a filename in unix?
I googled and found the following but its not sorting,also not sure what is the below command doing..any better ways using awk or anyother unix tool?
cut -d, -f1 file | uniq | xargs -I{} grep -m 1 "{}" file
On a side note,is there one that can be used in both windows and unix?this is not important but just checking..
C:\Users\Chola>sort -t "#" -k2,2 email-list.txt
Input text file:-
436485
422636
429228
427041
433414
425810
422636
431526
428808
If your file consists only of numbers, one per line:
sort -n FILENAME | uniq
or
sort -u -n FILENAME
(You can add -u to the sort command instead of piping through uniq in all of the following.).
If you want to extract just one column of a file, and then sort that column numerically removing duplicates, you could do this:
cut -f7 FILENAME | sort -n | uniq
Cut assumes that there is a single tab between columns. If your file is CSV, you might be able to do this:
cut -f7 -d, FILENAME | sort -n | uniq
but that won't work if there is a , in a text field in the file (where CSV will protect it with "'s).
If you want to sort by the column but remove only completely duplicate lines, then you can do this:
sort -k7,7n FILENAME | uniq
sort assumes that columns are separated by whitespace. Again, if you want to separate with ,, you can use:
sort -k7,7n -t, FILENAME | uniq

How to get the logged in user's real name in Unix?

I'm looking to find out the logged in user's real (full name) to avoid having to prompt them for it in an app I'm building. I see the finger command will output a columned list of data that includes this and was wondering if it makes sense to grep through this or is there an easier way? None of the switches for finger that I've found output just the real name. Any thoughts would be much appreciated.
getent passwd `whoami` | cut -d : -f 5
(getent is usually preferable to grepping /etc/passwd).
getent passwd "$USER" | cut -d: -f5 | cut -d, -f1
This first fetches the current user's line from the passwd database (which might also be stored on NIS or LDAP)
In the fetched line, fields are separated by : delimiters. The GECOS entry is the 5th field, thus the first cut extracts that.
The GECOS entry itself is possibly composed of multiple items - separated by , - of which the full name is the first item. That's what the second cut extracts. This also works if the GECOS entry is lacking the commas. In that case the whole entry is the first item.
You can also assign the result to a variable:
fullname=$( getent passwd "$USER" | cut -d: -f5 | cut -d, -f1 )
Or process it further directly:
echo "$( getent passwd "$USER" | cut -d: -f5 | cut -d, -f1 )'s home is $HOME."
cat <<EOF
Hello, $( getent passwd "$USER" | cut -d: -f5 | cut -d, -f1 ).
How are you doing?
EOF
You can use getpwent() to get each successive password entry until you find the one that matches the currently logged in user, then parse the gecos field.
Better, you can use getpwuid() to directly get the entry for the uid of the current user.
In either case,
You have to first get the current user's login name or id, and
There is no guarantee that the gecos field actually contains the user's real full name, or anything at all.
Specific to macOS, there is no getent command; instead you have to use id -F
For macOS and Linux:
if [ "Darwin" = $(uname) ]; then
FULLNAME=$(id -P $USER | awk -F '[:]' '{print $8}')
else
FULLNAME=$(getent passwd $USER | cut -d: -f5 | cut -d, -f1)
fi
echo $FULLNAME
I use
grep "^$USER:" /etc/passwd | awk -F: '{print $5}'
Explanations:
$USER contains the login of the current user
The first part (grep) extract from /etc/passwd the line about that user
The second part (awk) splits this line with separator ':' and prints the 5th component,
which is the full name
If you don't want to rely on $USER being set, you can use that instead:
grep "^`whoami`:" /etc/passwd | awk -F: '{print $5}'
How about trying whoami or logname

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