How can I use IFS and awk $2 value on the same line?
ex.
array=(
element:5001
element:5002
element:5003
element:5004
)
IFS=':'
for i in "${array[#]}"
do
set -- $i
part1=$1
part2=$2
cd $part1
# this following line is where I am having the issue.
# $2 equal to part2 from the string split, but the $2 to be
# awk value for $2
echo "$(ps aux | grep '[s]omething --port '$2'' | awk '{print $2}')"
# use part2 later in code
done
Presently, I am only able to use $2 from IFS split.
Note: I have seen post about using the -v option with awk but I believe that is when you want to set a value to run against awk. I would like to print $2 generated from awk.
Thanks to #Barmar and #l0b0.
I need to fix my quotes.
...
echo $(ps aux | grep '[s]omething --port '$2 | awk '{print $2}')
...
Related
I have a text file which contains the following lines:
"user","password_last_changed","expires_in"
"jeffrey","2021-09-21 12:54:26","90 days"
"root","2021-09-21 11:06:57","0 days"
How can I grab two fields jeffrey and 90 days from inverted commas and save in a variable.
If awk is an option, you could save an array and then save the elements as individual variables.
$ IFS="\"" read -ra var <<< $(awk -F, '/jeffrey/{ print $1, $NF }' input_file)
$ $ var2="${var[3]}"
$ echo "$var2"
90 days
$ var1="${var[1]}"
$ echo "$var1"
jeffrey
while read -r line; do # read in line by line
name=$(echo $line | awk -F, ' { print $1} ' | sed 's/"//g') # grap first col and strip "
expire=$(echo $line | awk -F, ' { print $3} '| sed 's/"//g') # grap third col and strip "
echo "$name" "$expire" # do your business
done < yourfile.txt
IFS=","
arr=( $(cat txt | head -2 | tail -1 | cut -d, -f 1,3 | tr -d '"') )
echo "${arr[0]}"
echo "${arr[1]}"
The result is into an array, you can access to the elements by index.
May be this below method will help you using
sed and awk command
#!/bin/sh
username=$(sed -n '/jeffrey/p' demo.txt | awk -F',' '{print $1}')
echo "$username"
expires_in=$(sed -n '/jeffrey/p' demo.txt | awk -F',' '{print $3}')
echo "$expires_in"
Output :
jeffrey
90 days
Note :
This above method will work if their is only distinct username
As far i know username are not duplicate
Here is my string that needs to be parsed.
line='aaa vvv ccc'
I need to print the values one by one.
no_of_users=$(echo $line| wc -w)
If the no_of_users is greater than 1 then I need to print the values one by one.
aaa
vvv
ccc
I used this script.
if [ $no_of_users -gt 1 ]
then
for ((n=1;n<=$no_of_users;n++))
do
-- here is my issue ##echo 'user:'$n $line|awk -F ' ' -vno="${n}" 'BEGIN { print no }'
done
fi
In the { print no } I have to print the value in that position.
You may use this awk:
awk 'NF>1 {OFS="\n"; $1=$1} 1' <<< "$line"
aaa
vvv
ccc
What it does:
NF>1: If number of fields are greater than 1
OFS="\n": Set output field separator to \n
$1=$1: Force restructure of a record
1: Print a record
1st solution: Within single awk could you please try following. Where var is an awk variable which has shell variable line value in it.
awk -v var="$line" '
BEGIN{
num=split(var,arr," ")
if(num>1){
for(i=1;i<=num;i++){ print arr[i] }
}
}'
Explanation: Adding detailed explanation for above.
awk -v var="$line" ' ##Starting awk program and creating var variable which has line shell variable value in it.
BEGIN{ ##Starting BEGIN section of program from here.
num=split(var,arr," ") ##Splitting var into array arr here. Saving its total length into variable num to check it later.
if(num>1){ ##Checking condition if num is greater than 1 then do following.
for(i=1;i<=num;i++){ print arr[i] } ##Running for loop from i=1 to till value of num here and printing arr value with index i here.
}
}'
2nd solution: Adding one more solution tested and written in GNU awk.
echo "$line" | awk -v RS= -v OFS="\n" 'NF>1{$1=$1;print}'
Another option:
if [ $no_of_users -gt 1 ]
then
for ((n=1;n<=$no_of_users;n++))
do
echo 'user:'$n $(echo $line|awk -F ' ' -v x=$n '{printf $x }')
done
fi
You can use grep
echo $line | grep -o '[a-z][a-z]*'
Also with awk:
awk '{print $1, $2, $3}' OFS='\n' <<< "$line"
aaa
vvv
ccc
the key is setting OFS='\n'
Or a really toughie:
printf "%s\n" $line
(note: $line is unquoted)
printf will consume all words in line with word-splitting applied so each word is taken as a single input.
Example Use/Output
$ line='aaa vvv ccc'; printf "%s\n" $line
aaa
vvv
ccc
Using bash:
$ line='aaa vvv'ccc'
$ [[ $line =~ \ ]] && echo -e ${line// /\\n}
aaa
vvv
ccc
$ line=aaa
$ [[ $line =~ \ ]] && echo -e ${line// /\\n}
$
If you are on another shell:
$ line="foo bar baz" bash -c '[[ $line =~ \ ]] && echo -e ${line// /\\n}'
grep -Eq '[[:space:]]' <<< "$line" && xargs printf "%s\n" <<< $line
Do a silent grep for a space in the variable, if true, print with names on separate lines.
awk -v OFS='\n' 'NF>1{$1=$1; print}'
e.g.
$ line='aaa vvv ccc'
$ echo "$line" | awk -v OFS='\n' 'NF>1{$1=$1; print}'
aaa
vvv
ccc
$ line='aaa'
$ echo "$line" | awk -v OFS='\n' 'NF>1{$1=$1; print}'
$
another golfed awk variation
$ awk 'gsub(FS,RS)'
only print if there is a substitution.
I run my safe shell script to make sure a binary is running
to check a binary is running I do following command
pidof prog.bin | awk '{print NF}'
is some system it gives me 0 when binary not running
and
in some systems it gives me NULL(nothing)
I can check the NULL using -z option but why awk command acting this way ??
Instead of pidof you can use:
pgrep -qf prog.bin
And check its exit status.
As per man pgrep:
-f Match against full argument lists. The default is to match against process names.
-q Do not write anything to standard output.
You can use this,
if [ `pidof 'NetworkManager'` ]; then
echo "Running"
else
echo "Not Running"
fi
One way to handle this sort of thing (undefined variables) in awk is like this:
echo hi | awk '{print a}'
compared with:
echo hi | awk '{print a || 0}'
0
One Liner for If else
[[ $(pidof 'NetworkManager') ]] && echo "Running" || echo "Not Running"
Try this:
pidof prog.bin | awk '{ if (NF!=0) print NF }'
Here's some tests with awk and NF:
$ # regular line of input
$ echo foo | awk '{print NF}'
1
$ # empty line
$ echo | awk '{print NF}'
0
$ # a word on input with no newline
$ printf "%s" nonewline | awk '{print NF}'
1
$ # no input, not even a newline
$ printf %s | awk '{print NF}'
# no output from awk
I suspect the pidof case is the last: not even a newline. To force a newline:
echo $(pidof prog) | ...
printf "%s\n" "$(pidof prog)" | ...
I have this command which executes correctly if run directly on the terminal.
awk '/word/ {print NR}' file.txt | head -n 1
The purpose is to find the line number of the line on which the word 'word' first appears in file.txt.
But when I put it in a script file, it doens't seem to work.
#! /bin/sh
if [ $# -ne 2 ]
then
echo "Usage: $0 <word> <filename>"
exit 1
fi
awk '/$1/ {print NR}' $2 | head -n 1
So what did I do wrong?
Thanks,
Replace the single quotes with double quotes so that the $1 is evaluated by the shell:
awk "/$1/ {print NR}" $2 | head -n 1
In the shell, single-quotes prevent parameter-substitution; so if your script is invoked like this:
script.sh word
then you want to run this AWK program:
/word/ {print NR}
but you're actually running this one:
/$1/ {print NR}
and needless to say, AWK has no idea what $1 is supposed to be.
To fix this, change your single-quotes to double-quotes:
awk "/$1/ {print NR}" $2 | head -n 1
so that the shell will substitute word for $1.
You should use AWK's variable passing feature:
awk -v patt="$1" '$0 ~ patt {print NR; exit}' "$2"
The exit makes the head -1 unnecessary.
you could also pass the value as a variable to awk:
awk -v varA=$1 '{if(match($0,varA)>0){print NR;}}' $2 | head -n 1
Seems more cumbersome than the above, but illustrates passing vars.
I'm trying to pass a variable to nawk in a bash script, but it's not actually printing the $commentValue variable's contents. Everything works great, except the last part of the printf statement. Thanks!
echo -n "Service Name: "
read serviceName
echo -n "Comment: "
read commentValue
for check in $(grep "CURRENT SERVICE STATE" $nagiosLog |grep -w "$serviceName" | nawk -F": " '{print $2}' |sort -u ) ; do
echo $check | nawk -F";" -v now=$now '{ printf( "[%u]=ACKNOWLEDGE_SVC_PROBLEM;"$1";"$2";2;1;0;admin;$commentValue"\n", now)}' >> $nagiosCommand
done
$commentValue is inside an invocation to nawk, so it is considered as a variable in nawk, not a variable in bash. Since you do not have such a variable in nawk, you won't get anything there. You should first pass the variable "inside" nawk using the -v switch just like you did for the now variable; i.e.:
... | nawk -F";" -v now=$now -v "commentValue=$commentValue"
Note the quotes - they are required in case $commentValue contains whitespace.