What is the usage of sorted command? - linux

I have read most of the example comes with sort command. How ever I am not sure what is the usage of sort command in this style?
sort <word> sorted

That would just be two file names, as in
sort file1 file2 file3...
If you pass multiple file names, sort concatenates them and sorts all of them together.

If you're asking how to sort a string with the sort command:
echo "tatoine" | grep -o . | sort | tr -d "\n"
aeinott
because sort operate on lines so you've got to cut the string in multiple lines with one letter on each (grep -o .) and after sorting you just delete the new lines with the tr command.

Are those < and > symbols explicit, or do they indicate a parameter that is to be replaced? If the latter, then you're reading from a file called "word", and writing the sorted data to a file called "sorted".

Are you trying to save the content in a sorted order?
Let's say you have a file name.txt with the following content.
Zoe
John
Amy
Mary
Mark
Peter
You can use the sort commmand "sort name.txt" and the output goes to the console
You can save the output using "sort name.txt -o sortedname.txt"
e.g.
Amy
John
Mark
mary
Peter
Zoe
You can found more option with the command "man sort" and "info sort"
rojomoke was right about the > and < commands. Those are redirection commands.
We usually read the data from standard input (stdin) and output goes to standard output aka the screen (stdout)
< means get the data from somewhere else. e.g. a file.
> means redirect the output to somewhere else e.g. a file.
So for the command above "sort name.txt -o sortedname.txt", I could have written as follow.
sort < name.txt > sortedname.txt
You can read more about the redirection in this wiki entry.
https://en.wikipedia.org/wiki/Redirection_(computing)
Commands like | >> will come in handy down the road.

Related

Can you use 'less' or 'more' to output one page worth of text?

So in Linux, less is used to read files page by page for better readability. I was wondering if you can do something like less file.txt > output.txt to get one page worth of file.txt and output/write it to `output.txt.
Apparently, this does not work, output.txt is exactly the same as the original file, I'm wondering why this is the case, and if there are other work-arounds. Thank you!
You can use the split command.
split -l 100 -d -a 3 input output
This will split the input file every 100 lines (-l 100), will use numbers as suffixes (-d) and will use 3 numbers as suffix (-a 3) in the output file. Something like this output000, output001, output002
You can use head to get a specific number of lines, and tput lines to see how many lines there are on your current terminal.
Here's a script that fetches a pageful, or the standard 25 lines if no terminal is available:
#!/bin/bash
lines=$(tput lines) || lines=25
head -n "$lines" file.txt > output.txt
we use head and tail to get n lines of top or bottom part of a file
cat /var/log/messages|tail -n20
head -n10 src/main.h

cat | sort csv file by name in bash

i have a bunch of csv files that i want to save them in one file ordered by name
i use
cat *.csv | sort -t\ -k2 -n *.csv > output.csv
works good for a naming like a001, a002, a010. a100
but in my files the names are fup a bit so they are like a1. a2. a10. a100
and the command i wrote will arrange my things like this:
cn201
cn202
cn202
cn203
cn204
cn99
cn98
cn97
cn96
..
cn9
can anyone please help me ?
Thanks
If I understand correctly, you want to use the -V (version-sort) flag instead of -n. This is only available on GNU sort, but that's probably the one you are using.
However, it depends how you want the prefixes to be sorted.
If you don't have the -V option, sort allows you to be more precise about what characters constitute a sort key.
sort -t\ -k2.3n *.csv > output.csv
The .3 tells sort that the key to sort on starts with the 3rd character of the second field, effectively skipping the cn prefix. You can put the n directly in the field specifier, which saves you two whole characters, but more importantly for more complex sorts, allows you to treat just that key as a number, rather than applying -n globally (which is only an issue if you specify multiple keys with several uses of -k).
The sort version on the live server is 5.97 from 2006
so few things did not work correctly.
However the code bellow is my solution
#!/bin/bash
echo "This script reads all CSVs into a single file (clusters.csv) in this directory"
for filers in *.csv
do
echo "" >> clusters.csv
echo "--------------------------------" >> clusters.csv
echo $filers >> largefile.txt
echo "--------------------------------" >> clusters.csv
cat $filers >> clusters.csv
done
or if you want to keep it simple inside one command
awk 'FNR > 1' *.csv > clusers.csv

How to find the particular text stored in the file "data.txt" and it occurs only once

The line I seek is stored in the file data.txt and is the only line of text that occurs only once.
How do I go about finding that particular line using linux?
This is a little bit old, but I think you are looking for this...
cat data.txt | sort | uniq -u
This will show the unique values that only occur once in the file. I assume you are familiar with "over the wire" if you are asking?? If so, this is what you are looking for.
To provide some context (I need more rep to comment) this is a question that features in an online "wargame" called Bandit that involves using the command line to discover passwords on an online Linux server to advance up the levels.
For those who would like to see data.txt in full I've Pastebin'd it here however it looks like this:
NN4e37KW2tkIb3dC9ZHyOPdq1FqZwq9h
jpEYciZvDIs6MLPhYoOGWQHNIoQZzE5q
3rpovhi1CyT7RUTunW30goGek5Q5Fu66
JOaWd4uAPii4Jc19AP2McmBNRzBYDAkO
JOaWd4uAPii4Jc19AP2McmBNRzBYDAkO
9WV67QT4uZZK7JHwmOH0jnhurJMwoGZU
a2GjmWtTe3tTM0ARl7TQwraPGXgfkH4f
7yJ8imXc7NNiovDuAl1ZC6xb0O0mMBx1
UsvVyFSfZZWbi6wgC7dAFyFuR6jQQUhR
FcOJhZkHlnwqcD8QbvjRyn886rCrnWZ7
E3ugYDa6Wh2y8C8xQev7vOS8O3OgG1Hw
E3ugYDa6Wh2y8C8xQev7vOS8O3OgG1Hw
ME7nnzbId4W3dajsl6Xtviyl5uhmMenv
J5lN3Qe4s7ktiwvcCj9ZHWrAJcUWEhUq
aouHvjzagN8QT2BCMB6e9rlN4ffqZ0Qq
ZRF5dlSuwuVV9TLhHKvPvRDrQ2L5ODfD
9ZjR3NTHue4YR6n4DgG5e0qMQcJjTaiM
QT8Bw9ofH4x3MeRvYAVbYvV1e1zq3Xim
i6A6TL6nqvjCAPvOdXZWjlYgyvqxmB7k
tx7tQ6kgeJnC446CHbiJY7fyRwrwuhrs
One way to do it is to use:
sort data.txt | uniq -u
The sort command is like cat in that it displays the contents of the file however it sorts the file lexicographically by lines (it reorders them alphabetically so that matching ones are together).
The | is a pipe that redirects the output from one command into another.
The uniq command reports or omits repeated lines and by passing it the -u argument we tell it to report only unique lines.
Used together like this, the command will sort data.txt lexicographically by each line, find the unique line and print it back in the terminal for you.
sort -u data.txt | while read line; do if [ $(grep -c $line data.txt) == 1 ] ;then echo $line; fi; done
was mine solution, until I saw here easy one:
sort data.txt | uniq -u
Add more information to you post.
How data.txt look like?
Like this:
11111111
11111111
pass1111
11111111
Or like this
afawfdgd
password
somethin
gelse...
And, do you know the password is in file or you search for not repeat string.
If you know password, use something like this
cat data.txt | grep 'password'
If you don`t know the password and this password is only unique line in file you must create a script.
For example in Python
file = open("data.txt","r")
f = file.read()
for line in f:
if 'pass' in line:
print pass
Of course replace pass with something else.
For example some slice from line.
And one with only one tool in use, awk:
awk '{a[$1]++}END{for(i in a){if(a[i] == 1){print i} }}' data.txt
sort data.txt | uniq -c | grep 1\ ?*
and it will print the only text that occurs only one time
do not forget to put space after the backslash
sort data.txt | uniq -c | grep 1
you will find only one that accures one time

How to compare two text files for the same exact text using BASH?

Let's say I have two text files that I need to extract data out of. The text of the two files is as follows:
File 1:
1name - randomemail#email.com
2Name - superrandomemail#email.com
3Name - 123random#email.com
4Name - random123#email.com
File 2:
email.com
email.com
email.com
anotherwebsite.com
File 2 is File 1's list of domain names, extracted from the email addresses.
These are not the same domain names by any means, and are quite random.
How can I get the results of the domain names that match File 2 from File 1?
Thank you in advance!
Assuming that order does not matter,
grep -F -f FILE2 FILE1
should do the trick. (This works because of a little-known fact: the -F option to grep doesn't just mean "match this fixed string," it means "match any of these newline-separated fixed strings.")
The recipe:
join <(sed 's/^.*#//' file1|sort -u) <(sort -u file2)
it will output the intersection of all domain names in file1 and file2
See BashFAQ/036 for the list of usual solutions to this type of problem.
Use VimDIFF command, this gives a nice presentation of difference
If I got you right, you want to filter for all addresses with the host mentioned in File 2.
You could then just loop over File 2 and grep for #<line>, accumulating the result in a new file or something similar.
Example:
cat file2 | sort -u | while read host; do grep "#$host" file1; done > filtered

Diff-ing files with Linux command

What Linux command allow me to check if all the lines in file A exist in file B? (it's almost like a diff, but not quite). Also file A has uniq lines, as is the case with file B as well.
The comm command compares two sorted files, line by line, and is part of GNU coreutils.
Are you looking for a better diff tool?
https://stackoverflow.com/questions/12625/best-diff-tool
So, what if A has
a
a
b
and b has
a
b
What would you want the output to be(yes or no)?
Use diff command.
Here is a useful vide with complete usage of diff command under 3 min
Click Here
if cat A A B | sort | uniq -c | egrep -e '^[[:space:]]*2[[:space:]]' > /dev/null; then
echo "A has lines that are not in B."
fi
If you do not redirect the output, you will get a list of all the lines that are in A that are not in B (except each line will have a 2 in front if it). This relies on the lines in A being unique, and the lines in B being unique.
If they aren't, and you don't care about counting duplicates, it's relatively simple to transform each file into a list of unique lines using sort and uniq.

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