I need to look at a line, and perform a quick if/then->echo on it depending on the content of column 3.
The file looks like this:
name network subnetmask
net_A 192.168.0.0 24
net_b 10.10.0.0 16
Some columns also have a blank 3rd column, and I need to have an if/then for those as well.
Psuedo-code should look like this in my mind:
snet_mask=`cat $filename | grep -i net | awk '{print $3}`
if [ $snet_mask = 24 ]
then
awk '{print "something"$1,"something else"}'
fi
if [ $snet_mask = 23 ]
then
awk '{print "something"$1,"something else"}'
fi
etc
That just doesn't work it seems, since $snet_mask becomes the value of "all" of $3, so I think I need a for loop based on grep -i net, however I don't really know.
What's the right answer? :)
Try this one-liner :
awk '$1 ~ "^net" && $3==24{print "something", $3, "something else"} $1 ~ "^net" $3==23{print "something", $3, "something else"}' file.txt
Or on multi-lines (easier to read) :
awk '
$1 ~ "^net" && $3==24{print "something", $3, "something else"}
$1 ~ "^net" && $3==23{print "something", $3, "something else"}
' file.txt
We can do it simply like this too (depends of your needs) :
awk '
$1 ~ "^net" && ($3==24 || $3==23) {print "something", $3, "something else"}
' file.txt
Or even simpler & shortest with a regex :
awk '
$1 ~ "net" && $3 ~ "^2[34]$" {print "something", $3, "something else"}
' file.txt
you could accomplish what you need in an awk statement, since you're already using awk
cat $filename | grep -i net | awk '{if($3==24) print $1; else print $0;}'
In the if statement (if 3rd col is 23), I'm printing just the first column, otherwise I'm printing everything. Obviously you can expand this to work with all of your cases
Staying in bash without external tools, you could do something like this:
while read name network netmask ; do
if [[ "$name" == net* ]] ; then
case "$netmask" in
"") echo "It's empty" ;;
24) echo "It's 24" ;;
23) echo "It's 23" ;;
*) echo "None of the above" ;;
esac
fi
done < "$filename"
Related
The cmd:
STATUS=`grep word a.log | tail -1 | awk '{print $1,$2,$7,$8,$9}'`
echo "$STATUS"
The output:
2020-05-18 09:27:01 1 of 122
I need to display this $STATUS and need to do the test comparison as well.
How to compare number 122 in below? How to represent 122 in $X?
The number 122 can be any number, resulted from above cmd.
if [ "$X" -gt "300" ]
then
echo "$STATUS. This in HIGH queue ($X)"
else
echo "$STATUS. This is NORMAL ($X)"
fi
You could do it with one awk script:
awk '
/word/{ status=$1" "$2" "$7" "$8" "$9; x=$9 }
END{ printf status". This %s (%s)\n", (x>300 ? "in HIGH queue" : "is NORMAL"), x }
' a.log
I would suggest using lowercase for variables to reduce possible confusion for someone other than the original author reading the script in the future. Also using $() is typically preferable to using back-ticks -- makes quoting easier to get right.
status="$(grep word a.log | tail -1 | awk '{print $1,$2,$7,$8,$9}')"
x="$(printf '%s' "$status" | awk '{ print $NF }')"
if [ "$x" -gt 300 ]
then
echo "$status. This in HIGH queue ($x)"
else
echo "$status. This is NORMAL ($x)"
fi
Note -- we could refactor the status line a bit:
status="$(awk '/word/ { x = $1 OFS $2 OFS $7 OFS $8 OFS $9 } END { print x }' a.log)"
Egrep and Awk to output columns of a line , with a specific value for the first column
I am to tasked to write a shell program which when ran as such
./tool.sh -f file -id id OR ./tool.sh -id id -f file
must output the name surname and birthdate (3 columns of the file ) for that specific id.
So far my code is structured as such :
elif [ "$#" -eq 4 ];
then
while [ "$1" != "" ];
do
case $1 in
-f)
cat < "$2" | egrep '"$4"' | awk ' {print $3 "\t" $2 "\t" $5}'
shift 4
;;
-id)
cat < "$4" | egrep '"$2"' | awk ' {print $3 "\t" $2 "\t" $5}'
shift 4
esac
done
(Ignoring the opening elif cause there are more subtasks for later)
My output is nothing. The program just runs.
I've tested the cat < people.dat | egrep '125' | awk ' {print $3 "\t" $2 "\t" $5}'
and it runs just fine.
I also had an instance where i had an output from the program while it was run like so
cat < "$2" | egrep '["$4"]' | awk ' {print $3 "\t" $2 "\t" $5}'
but it wasnt only that specific ID.
`egrep "$4"` was correct instead of `egrep '["$4"]'` in
`cat < "$2" | egrep '["$4"]' | awk ' {print $3 "\t" $2 "\t" $5}'`
Double quotes allow variables, single quotes don't. No commands need
certain types of quotes, they are purely a shell feature that are not
passed to the command. mentioned by(#that other guy)
I have this until now:
if [[ $1 = "-s" ]] && [[ $2 =~ ^[0-9]+$ ]]
echo "ok"
for $2 = 1 awk {print $1} something.txt
fi
What I want is, for example, when I enter -s 2, to list the second word of every line first!
I already know the for part is wrong.
Replace
for $2 = 1 awk {print $1} something.txt
by
awk -v var="$2" '{print $var}' something.txt
I'm using the following awk command:
my_command | awk -F "[[:space:]]{2,}+" 'NR>1 {print $2}' | egrep "^[[:alnum:]]"
which successfully returns my data like this:
fileName1
file Name 1
file Nameone
f i l e Name 1
So as you can see some file names have spaces. This is fine as I'm just trying to echo the file name (nothing special). The problem is calling that specific row within a loop. I'm trying to do it this way:
i=1
for num in $rows
do
fileName=$(my_command | awk -F "[[:space:]]{2,}+" 'NR==$i {print $2}' | egrep "^[[:alnum:]])"
echo "$num $fileName"
$((i++))
done
But my output is always null
I've also tried using awk -v record=$i and then printing $record but I get the below results.
f i l e Name 1
EDIT
Sorry for the confusion: rows is a variable that list ids like this 11 12 13
and each one of those ids ties to a file name. My command without doing any parsing looks like this:
id File Info OS
11 File Name1 OS1
12 Fi leNa me2 OS2
13 FileName 3 OS3
I can only use the id field to run a the command that I need, but I want to use the File Info field to notify the user of the actual File that the command is being executed against.
I think your $i does not expand as expected. You should quote your arguments this way:
fileName=$(my_command | awk -F "[[:space:]]{2,}+" "NR==$i {print \$2}" | egrep "^[[:alnum:]]")
And you forgot the other ).
EDIT
As an update to your requirement you could just pass the rows to a single awk command instead of a repeatitive one inside a loop:
#!/bin/bash
ROWS=(11 12)
function my_command {
# This function just emulates my_command and should be removed later.
echo " id File Info OS
11 File Name1 OS1
12 Fi leNa me2 OS2
13 FileName 3 OS3"
}
awk -- '
BEGIN {
input = ARGV[1]
while (getline line < input) {
sub(/^ +/, "", line)
split(line, a, / +/)
for (i = 2; i < ARGC; ++i) {
if (a[1] == ARGV[i]) {
printf "%s %s\n", a[1], a[2]
break
}
}
}
exit
}
' <(my_command) "${ROWS[#]}"
That awk command could be condensed to one line as:
awk -- 'BEGIN { input = ARGV[1]; while (getline line < input) { sub(/^ +/, "", line); split(line, a, / +/); for (i = 2; i < ARGC; ++i) { if (a[1] == ARGV[i]) {; printf "%s %s\n", a[1], a[2]; break; }; }; }; exit; }' <(my_command) "${ROWS[#]}"
Or better yet just use Bash instead as a whole:
#!/bin/bash
ROWS=(11 12)
while IFS=$' ' read -r LINE; do
IFS='|' read -ra FIELDS <<< "${LINE// +( )/|}"
for R in "${ROWS[#]}"; do
if [[ ${FIELDS[0]} == "$R" ]]; then
echo "${R} ${FIELDS[1]}"
break
fi
done
done < <(my_command)
It should give an output like:
11 File Name1
12 Fi leNa me2
Shell variables aren't expanded inside single-quoted strings. Use the -v option to set an awk variable to the shell variable:
fileName=$(my_command | awk -v i=$i -F "[[:space:]]{2,}+" 'NR==i {print $2}' | egrep "^[[:alnum:]])"
This method avoids having to escape all the $ characters in the awk script, as required in konsolebox's answer.
As you already heard, you need to populate an awk variable from your shell variable to be able to use the desired value within the awk script so thi:
awk -F "[[:space:]]{2,}+" 'NR==$i {print $2}' | egrep "^[[:alnum:]]"
should be this:
awk -v i="$i" -F "[[:space:]]{2,}+" 'NR==i {print $2}' | egrep "^[[:alnum:]]"
Also, though, you don't need awk AND grep since awk can do anything grep van do so you can change this part of your script:
awk -v i="$i" -F "[[:space:]]{2,}+" 'NR==i {print $2}' | egrep "^[[:alnum:]]"
to this:
awk -v i="$i" -F "[[:space:]]{2,}+" '(NR==i) && ($2~/^[[:alnum:]]/){print $2}'
and you don't need a + after a numeric range so you can change {2,}+ to just {2,}:
awk -v i="$i" -F "[[:space:]]{2,}" '(NR==i) && ($2~/^[[:alnum:]]/){print $2}'
Most importantly, though, instead of invoking awk once for every invocation of my_command, you can just invoke it once for all of them, i.e. instead of this (assuming this does what you want):
i=1
for num in rows
do
fileName=$(my_command | awk -v i="$i" -F "[[:space:]]{2,}" '(NR==i) && ($2~/^[[:alnum:]]/){print $2}')
echo "$num $fileName"
$((i++))
done
you can do something more like this:
for num in rows
do
my_command
done |
awk -F '[[:space:]]{2,}' '$2~/^[[:alnum:]]/{print NR, $2}'
I say "something like" because you don't tell us what "my_command", "rows" or "num" are so I can't be precise but hopefully you see the pattern. If you give us more info we can provide a better answer.
It's pretty inefficient to rerun my_command (and awk) every time through the loop just to extract one line from its output. Especially when all you're doing is printing out part of each line in order. (I'm assuming that my_command really is exactly the same command and produces the same output every time through your loop.)
If that's the case, this one-liner should do the trick:
paste -d' ' <(printf '%s\n' $rows) <(my_command |
awk -F '[[:space:]]{2,}+' '($2 ~ /^[::alnum::]/) {print $2}')
My goal is to find out the length of the second field and if the length is more than five characters, then I need to show the entire record using shell scripts/command.
echo "From the csv file"
cat latency.csv |
while read line
do
latency=`echo $line | cut -d"," -f2 | tr -d " "`
length=$(echo ${#latency})
if [ $length -gt 5 ]
then
echo $line
fi
done
There is nothing wrong with my code, but being UNIX/Linux, I thought there should be a simpler way of doing such things.
Is there one such simpler method?
awk -F, 'length($2)>5' file
this should work
updated
awk -F, '{a=$0;gsub(/ /,"",$2);if(length($2)>5)print a}' file
awk -F, '{
t = $2
gsub(/ /, x, t)
if (length(t) > 5)
print
}' latency.csv
Or:
perl -F, -ane'
print if
$F[1] =~ tr/ //dc > 5
' latency.csv