I'm trying to create a simple shell script showing how many times a user has logged in to their linux machine for at least one week. The output of the shell script should be like this:
2021-12-16
****
2021-12-15
**
2021-12-14
*******
I have tried this so far but it shows only numeric but i want showing * symbols.
user="$1"
last -F | grep "${user}" | sed -E "s/${user}.*(Mon|Tue|Wed|Thu|Fri|Sat|Sun) //" | awk '{print $1"-"$2"-"$4}' | uniq -c
Any help?
You might want to refactor all of this into a simple Awk script, where repeating a string n times is also easy.
user="$1"
last -F |
awk -v user="$1" 'BEGIN { split("Jan:Feb:Mar:Apr:May:Jun:Jul:Aug:Sep:Oct:Nov:Dec", m, ":");
for(i=1; i<=12; i++) mon[m[i]] = sprintf("%02i", i) }
$1 == user { ++count[$8 "-" mon[$5] "-" sprintf("%02i", $6)] }
END { for (date in count) {
padded = sprintf("%-" count[date] "s", "*");
gsub(/ /, "*", padded);
print date, padded } }'
The BEGIN block creates an associative array mon which maps English month abbreviations to month numbers.
sprintf("%02i", number) produces the value of number with zero padding to two digits (i.e. adds a leading zero if number is a single digit).
The $1 == user condition matches the lines where the first field is equal to the user name we passed in. (Your original attempt had two related bugs here; it would look for the user name anywhere in the line, so if the user name happened to match on another field, it would erroneously match on that; and the regex you used would match a substring of a longer field).
When that matches, we just update the value in the associative array count whose key is the current date.
Finally, in the END block, we simply loop over the values in count and print them out. Again, we use sprintf to produce a field with a suitable length. We play a little trick here by space-padding to the specified width, because sprintf does that out of the box, and then replace the spaces with more asterisks.
Your desired output shows the asterisks on a separate line from the date; obviously, it's easy to change that if you like, but I would advise against it in favor of a format which is easy to sort, grep, etc (perhaps to then reformat into your desired final human-readable form).
If you have GNU sed you're almost there. Just pipe the output of uniq -c to this GNU sed command:
sed -En 's/^\s*(\S+)\s+(\S+).*/printf "\2\n%\1s" ""/e;s/ /*/g;p'
Explanation: in the output of uniq -c we substitute a line like:
6 Dec-15-2021
by:
printf "Dec-15-2021\n%6s" ""
and we use the e GNU sed flag (this is a GNU sed extension so you need GNU sed) to pass this to the shell. The output is:
Dec-15-2021
where the second line contains 6 spaces. This output is copied back into the sed pattern space. We finish by a global substitution of spaces by stars and print:
Dec-15-2021
******
A simple soluction, using tempfile
#!/bin/bash
user="$1"
tempfile="/tmp/last.txt"
IFS='
'
last -F | grep "${user}" | sed -E "s/"${user}".*(Mon|Tue|Wed|Thu|Fri|Sat|Sun) //" | awk '{print $1"-"$2"-"$4}' | uniq -c > $tempfile
for LINE in $(cat $tempfile)
do
qtde=$(echo $LINE | awk '{print $1'})
data=$(echo $LINE | awk '{print $2'})
echo -e "$data "
for ((i=1; i<=qtde; i++))
do
echo -e "*\c"
done
echo -e "\n"
done
I am wrote a simple script to extract text from a bunch of files (*.out) and add two lines at the beginning and a line at the end. Then I add the extracted text with another file to create a new file. The script is here.
#!/usr/bin/env bash
#A simple bash script to extract text from *.out and create another file
for f in *.out; do
#In the following line, n is a number which is extracted from the file name
n=$(echo $f | cut -d_ -f6)
t=$((2 * $n ))
#To extract the necessary text/data
grep " B " $f | tail -${t} | awk 'BEGIN {OFS=" ";} {print $1, $4, $5, $6}' | rev | column -t | rev > xyz.xyz
#To add some text as the first, second and last lines.
sed -i '1i -1 2' xyz.xyz
sed -i '1i $molecule' xyz.xyz
echo '$end' >> xyz.xyz
#To combine the extracted info with another file (ea_input.in)
cat xyz.xyz ./input_ea.in > "${f/abc.out/pqr.in}"
done
./script.sh: line 4: (ls file*.out | cut -d_ -f6: syntax error: invalid arithmetic operator (error token is ".out) | cut -d_ -f6")
How I can correct this error?
In bash, when you use:
$(( ... ))
it treats the contents of the brackets as an arithmetic expression, returning the result of the calculation, and when you use:
$( ... )
it executed the contents of the brackets and returns the output.
So, to fix your issue, it should be as simple as to replace line 4 with:
n=$(ls $f | cut -d_ -f6)
This replaces the outer double brackets with single, and removes the additional brackets around ls $f which should be unnecessary.
The arithmetic error can be avoided by adding spaces between parentheses. You are already using var=$((arithmetic expression)) correctly elsewhere in your script, so it should be easy to see why $( ((ls "$f") | cut -d_ -f6)) needs a space. But the subshells are completely superfluous too; you want $(ls "$f" | cut -d_ -f6). Except ls isn't doing anything useful here, either; use $(echo "$f" | cut -d_ -f6). Except the shell can easily, albeit somewhat clumsily, extract a substring with parameter substitution; "${f#*_*_*_*_*_}". Except if you're using Awk in your script anyway, it makes more sense to do this - and much more - in Awk as well.
Here is an at empt at refactoring most of the processing into Awk.
for f in *.out; do
awk 'BEGIN {OFS=" " }
# Extract 6th _-separated field from input filename
FNR==1 { split(FILENAME, f, "_"); t=2*f[6] }
# If input matches regex, add to array b
/ B / { b[++i] = $1 OFS $4 OFS $5 OFS $6 }
# If array size reaches t, start overwriting old values
i==t { i=0; m=t }
END {
# Print two prefix lines
print "$molecule"; print -1, 2;
# Handle array smaller than t
if (!m) m=i
# Print starting from oldest values (index i + 1)
for(j=1; j<=m; j++) {
# Wrap to beginning of array at end
if(i+j > t) i-=t
print b[i+j]; }
print "$end" }' "$f" |
rev | column -t | rev |
cat - ./input_ea.in > "${f/foo.out/bar.in}"
done
Notice also how we avoid using a temporary file (this would certainly have been avoidable without the Awk refactoring, too) and how we take care to quote all filename variables in double quotes.
The array b contains (up to) the latest t values from matching lines; we collect these into an array which is constrained to never contain more than t values by wrapping the index i back to the beginning of the array when we reach index t. This "circular array" avoids keeping too many values in memory, which would make the script slow if the input file contains many matches.
I am using 'df -h' command to get disk space details in my directory and it gives me response as below :
Now I want to be able to do this check automatically through some batch or script - so I am wondering, if I will be able to check disk space only for specific folders which I care about, as shown in image - I am only supposed to check for /nas/home that it does not go above 75%.
How can I achieve this ? Any help ?
My work till now:
I am using
df -h > DiskData.txt
... this outputs to a text file
grep "/nas/home" "DiskData.txt"
... which gives me the output:
*500G 254G 247G 51% /nas/home*
Now I want to be able to search for the number previous or right nearby '%' sign (51 in this case) to achieve what I want.
This command will give you percentage of /nas/home directory
df /nas/home | awk '{ print $4 }' | tail -n 1| cut -d'%' -f1
So basically you can use store as value in some variable and then apply if else condition.
var=`df /nas/home | awk '{ print $4 }' | tail -n 1| cut -d'%' -f1`
if(var>75){
#send email
}
another variant:
df --output=pcent /nas/home | tail -n 1 | tr -d '[:space:]|%'
output=pcent - show only percent value (for coreutils => 8.21 )
A more concise way without extensive piping could be:
df -h /nas/home | perl -ane 'print substr $F[3],0,-1 if $.==2'
Returns: 51 for your example.
I have a log file (from a customer). 18 Gigs. All contents of the file are in 1 line.
I want to read the file in logstash. But I get problems because of Memory. The file is read line by line but unfortunately it is all on 1 line.
I tried split the file into lines so that logstash can process it (the file has a simple json format, no nested objects) i wanted to have each json in one line, splitting at } by replacing with }\n:
sed -i 's/}/}\n/g' NonPROD.log.backup
But sed is killed - I assume also because of memory. How can I resolve this? Can I let sed manipulate the file using other chunks of data than lines? I know by default sed reads line by line.
The following uses only functionality built into the shell:
#!/bin/bash
# as long as there exists another } in the file, read up to it...
while IFS= read -r -d '}' piece; do
# ...and print that content followed by '}' and a newline.
printf '%s}\n' "$piece"
done
# print any trailing content after the last }
[[ $piece ]] && printf '%s\n' "$piece"
If you have logstash configured to read from a TCP port (using 14321 as an arbitrary example below), you can run thescript <NonPROD.log.backup >"/dev/tcp/127.0.0.1/14321" or similar, and there you are -- without needing to have double your original input file's space available on disk, as other answers thus far given require.
With GNU awk for RT:
$ printf 'abc}def}ghi\n' | awk -v RS='}' '{ORS=(RT?"}\n":"")}1'
abc}
def}
ghi
with other awks:
$ printf 'abc}def}ghi\n' | awk -v RS='}' -v ORS='}\n' 'NR>1{print p} {p=$0} END{printf "%s",p}'
abc}
def}
ghi
I decided to test all of the currently posted solutions for functionality and execution time using an input file generated by this command:
awk 'BEGIN{for(i=1;i<=1000000;i++)printf "foo}"; print "foo"}' > file1m
and here's what I got:
1) awk (both awk scripts above had similar results):
time awk -v RS='}' '{ORS=(RT?"}\n":"")}1' file1m
Got expected output, timing =
real 0m0.608s
user 0m0.561s
sys 0m0.045s
2) shell loop:
$ cat tst.sh
#!/bin/bash
# as long as there exists another } in the file, read up to it...
while IFS= read -r -d '}' piece; do
# ...and print that content followed by '}' and a newline.
printf '%s}\n' "$piece"
done
# print any trailing content after the last }
[[ $piece ]] && printf '%s\n' "$piece"
$ time ./tst.sh < file1m
Got expected output, timing =
real 1m52.152s
user 1m18.233s
sys 0m32.604s
3) tr+sed:
$ time tr '}' '\n' < file1m | sed 's/$/}/'
Did not produce the expected output (Added an undesirable } at the end of the file), timing =
real 0m0.577s
user 0m0.468s
sys 0m0.078s
With a tweak to remove that final undesirable }:
$ time tr '}' '\n' < file1m | sed 's/$/}/; $s/}//'
real 0m0.718s
user 0m0.670s
sys 0m0.108s
4) fold+sed+tr:
$ time fold -w 1000 file1m | sed 's/}/}\n\n/g' | tr -s '\n'
Got expected output, timing =
real 0m0.811s
user 0m1.137s
sys 0m0.076s
5) split+sed+cat:
$ cat tst2.sh
mkdir tmp$$
pwd="$(pwd)"
cd "tmp$$"
split -b 1m "${pwd}/${1}"
sed -i 's/}/}\n/g' x*
cat x*
rm -f x*
cd "$pwd"
rmdir tmp$$
$ time ./tst2.sh file1m
Got expected output, timing =
real 0m0.983s
user 0m0.685s
sys 0m0.167s
You can running it through tr, then put the end bracket back on at the end of each line:
$ cat NonPROD.log.backup | tr '}' '\n' | sed 's/$/}/' > tmp$$
$ wc -l NonPROD.log.backup tmp$$
0 NonPROD.log.backup
43 tmp10528
43 total
(My test file only had 43 brackets.)
You could:
Split the file to say 1M chunks using split -b 1m file.log
Process all the files sed 's/}/}\n/g' x*
... and redirect the output of sed to combine them back to a single piece
The drawback of this is the doubled storage space.
another alternative with fold
$ fold -w 1000 long_line_file | sed 's/}/}\n\n/g' | tr -s '\n'
I have a CSV file that looks like this
AS2345,ASDF1232, Mr. Plain Example, 110 Binary ave.,Atlantis,RI,12345,(999)123-5555,1.56
AS2345,ASDF1232, Mrs. Plain Example, 1121110 Ternary st. 110 Binary ave..,Atlantis,RI,12345,(999)123-5555,1.56
AS2345,ASDF1232, Mr. Plain Example, 110 Binary ave.,Liberty City,RI,12345,(999)123-5555,1.56
AS2345,ASDF1232, Mr. Plain Example, 110 Ternary ave.,Some City,RI,12345,(999)123-5555,1.56
I need to sort it by line length including spaces. The following command doesn't
include spaces, is there a way to modify it so it will work for me?
cat $# | awk '{ print length, $0 }' | sort -n | awk '{$1=""; print $0}'
Answer
cat testfile | awk '{ print length, $0 }' | sort -n -s | cut -d" " -f2-
Or, to do your original (perhaps unintentional) sub-sorting of any equal-length lines:
cat testfile | awk '{ print length, $0 }' | sort -n | cut -d" " -f2-
In both cases, we have solved your stated problem by moving away from awk for your final cut.
Lines of matching length - what to do in the case of a tie:
The question did not specify whether or not further sorting was wanted for lines of matching length. I've assumed that this is unwanted and suggested the use of -s (--stable) to prevent such lines being sorted against each other, and keep them in the relative order in which they occur in the input.
(Those who want more control of sorting these ties might look at sort's --key option.)
Why the question's attempted solution fails (awk line-rebuilding):
It is interesting to note the difference between:
echo "hello awk world" | awk '{print}'
echo "hello awk world" | awk '{$1="hello"; print}'
They yield respectively
hello awk world
hello awk world
The relevant section of (gawk's) manual only mentions as an aside that awk is going to rebuild the whole of $0 (based on the separator, etc) when you change one field. I guess it's not crazy behaviour. It has this:
"Finally, there are times when it is convenient to force awk to rebuild the entire record, using the current value of the fields and OFS. To do this, use the seemingly innocuous assignment:"
$1 = $1 # force record to be reconstituted
print $0 # or whatever else with $0
"This forces awk to rebuild the record."
Test input including some lines of equal length:
aa A line with MORE spaces
bb The very longest line in the file
ccb
9 dd equal len. Orig pos = 1
500 dd equal len. Orig pos = 2
ccz
cca
ee A line with some spaces
1 dd equal len. Orig pos = 3
ff
5 dd equal len. Orig pos = 4
g
The AWK solution from neillb is great if you really want to use awk and it explains why it's a hassle there, but if what you want is to get the job done quickly and don't care what you do it in, one solution is to use Perl's sort() function with a custom caparison routine to iterate over the input lines. Here is a one liner:
perl -e 'print sort { length($a) <=> length($b) } <>'
You can put this in your pipeline wherever you need it, either receiving STDIN (from cat or a shell redirect) or just give the filename to perl as another argument and let it open the file.
In my case I needed the longest lines first, so I swapped out $a and $b in the comparison.
Benchmark results
Below are the results of a benchmark across solutions from other answers to this question.
Test method
10 sequential runs on a fast machine, averaged
Perl 5.24
awk 3.1.5 (gawk 4.1.0 times were ~2% faster)
The input file is a 550MB, 6 million line monstrosity (British National Corpus txt)
Results
Caleb's perl solution took 11.2 seconds
my perl solution took 11.6 seconds
neillb's awk solution #1 took 20 seconds
neillb's awk solution #2 took 23 seconds
anubhava's awk solution took 24 seconds
Jonathan's awk solution took 25 seconds
Fritz's bash solution takes 400x longer than the awk solutions (using a truncated test case of 100000 lines). It works fine, just takes forever.
Another perl solution
perl -ne 'push #a, $_; END{ print sort { length $a <=> length $b } #a }' file
Try this command instead:
awk '{print length, $0}' your-file | sort -n | cut -d " " -f2-
Pure Bash:
declare -a sorted
while read line; do
if [ -z "${sorted[${#line}]}" ] ; then # does line length already exist?
sorted[${#line}]="$line" # element for new length
else
sorted[${#line}]="${sorted[${#line}]}\n$line" # append to lines with equal length
fi
done < data.csv
for key in ${!sorted[*]}; do # iterate over existing indices
echo -e "${sorted[$key]}" # echo lines with equal length
done
Python Solution
Here's a Python one-liner that does the same, tested with Python 3.9.10 and 2.7.18. It's about 60% faster than Caleb's perl solution, and the output is identical (tested with a 300MiB wordlist file with 14.8 million lines).
python -c 'import sys; sys.stdout.writelines(sorted(sys.stdin.readlines(), key=len))'
Benchmark:
python -c 'import sys; sys.stdout.writelines(sorted(sys.stdin.readlines(), key=len))'
real 0m5.308s
user 0m3.733s
sys 0m1.490s
perl -e 'print sort { length($a) <=> length($b) } <>'
real 0m8.840s
user 0m7.117s
sys 0m2.279s
The length() function does include spaces. I would make just minor adjustments to your pipeline (including avoiding UUOC).
awk '{ printf "%d:%s\n", length($0), $0;}' "$#" | sort -n | sed 's/^[0-9]*://'
The sed command directly removes the digits and colon added by the awk command. Alternatively, keeping your formatting from awk:
awk '{ print length($0), $0;}' "$#" | sort -n | sed 's/^[0-9]* //'
I found these solutions will not work if your file contains lines that start with a number, since they will be sorted numerically along with all the counted lines. The solution is to give sort the -g (general-numeric-sort) flag instead of -n (numeric-sort):
awk '{ print length, $0 }' lines.txt | sort -g | cut -d" " -f2-
With POSIX Awk:
{
c = length
m[c] = m[c] ? m[c] RS $0 : $0
} END {
for (c in m) print m[c]
}
Example
1) pure awk solution. Let's suppose that line length cannot be more > 1024
then
cat filename | awk 'BEGIN {min = 1024; s = "";} {l = length($0); if (l < min) {min = l; s = $0;}} END {print s}'
2) one liner bash solution assuming all lines have just 1 word, but can reworked for any case where all lines have same number of words:
LINES=$(cat filename); for k in $LINES; do printf "$k "; echo $k | wc -L; done | sort -k2 | head -n 1 | cut -d " " -f1
using Raku (formerly known as Perl6)
~$ cat "BinaryAve.txt" | raku -e 'given lines() {.sort(*.chars).join("\n").say};'
AS2345,ASDF1232, Mr. Plain Example, 110 Binary ave.,Atlantis,RI,12345,(999)123-5555,1.56
AS2345,ASDF1232, Mr. Plain Example, 110 Ternary ave.,Some City,RI,12345,(999)123-5555,1.56
AS2345,ASDF1232, Mr. Plain Example, 110 Binary ave.,Liberty City,RI,12345,(999)123-5555,1.56
AS2345,ASDF1232, Mrs. Plain Example, 1121110 Ternary st. 110 Binary ave..,Atlantis,RI,12345,(999)123-5555,1.56
To reverse the sort, add .reverse in the middle of the chain of method calls--immediately after .sort(). Here's code showing that .chars includes spaces:
~$ cat "number_triangle.txt" | raku -e 'given lines() {.map(*.chars).say};'
(1 3 5 7 9 11 13 15 17 19 0)
~$ cat "number_triangle.txt"
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9 0
Here's a time comparison between awk and Raku using a 9.1MB txt file from Genbank:
~$ time cat "rat_whole_genome.txt" | raku -e 'given lines() {.sort(*.chars).join("\n").say};' > /dev/null
real 0m1.308s
user 0m1.213s
sys 0m0.173s
~$ #awk code from neillb
~$ time cat "rat_whole_genome.txt" | awk '{ print length, $0 }' | sort -n -s | cut -d" " -f2- > /dev/null
real 0m1.189s
user 0m1.170s
sys 0m0.050s
HTH.
https://raku.org
Here is a multibyte-compatible method of sorting lines by length. It requires:
wc -m is available to you (macOS has it).
Your current locale supports multi-byte characters, e.g., by setting LC_ALL=UTF-8. You can set this either in your .bash_profile, or simply by prepending it before the following command.
testfile has a character encoding matching your locale (e.g., UTF-8).
Here's the full command:
cat testfile | awk '{l=$0; gsub(/\047/, "\047\"\047\"\047", l); cmd=sprintf("echo \047%s\047 | wc -m", l); cmd | getline c; close(cmd); sub(/ */, "", c); { print c, $0 }}' | sort -ns | cut -d" " -f2-
Explaining part-by-part:
l=$0; gsub(/\047/, "\047\"\047\"\047", l); ← makes of a copy of each line in awk variable l and double-escapes every ' so the line can safely be echoed as a shell command (\047 is a single-quote in octal notation).
cmd=sprintf("echo \047%s\047 | wc -m", l); ← this is the command we'll execute, which echoes the escaped line to wc -m.
cmd | getline c; ← executes the command and copies the character count value that is returned into awk variable c.
close(cmd); ← close the pipe to the shell command to avoid hitting a system limit on the number of open files in one process.
sub(/ */, "", c); ← trims white space from the character count value returned by wc.
{ print c, $0 } ← prints the line's character count value, a space, and the original line.
| sort -ns ← sorts the lines (by prepended character count values) numerically (-n), and maintaining stable sort order (-s).
| cut -d" " -f2- ← removes the prepended character count values.
It's slow (only 160 lines per second on a fast Macbook Pro) because it must execute a sub-command for each line.
Alternatively, just do this solely with gawk (as of version 3.1.5, gawk is multibyte aware), which would be significantly faster. It's a lot of trouble doing all the escaping and double-quoting to safely pass the lines through a shell command from awk, but this is the only method I could find that doesn't require installing additional software (gawk is not available by default on macOS).
Revisiting this one. This is how I approached it (count length of LINE and store it as LEN, sort by LEN, keep only the LINE):
cat test.csv | while read LINE; do LEN=$(echo ${LINE} | wc -c); echo ${LINE} ${LEN}; done | sort -k 2n | cut -d ' ' -f 1