I have string lists :
./SolutionController.php core/app/Http/Controllers/Admin/SolutionController.php
./ContentController.php core/app/Http/Controllers/Frontpage/ContentController.php
./country-flag vendor/country-flag
I wish I could get the final value between the './' sign and the 'space'
Output:
SolutionController.php
ContentController.php
country-flag
This code with bash script:
#!/bin/bash
tanggal=$(date +%d-%m-%Y)
filename="./update/$tanggal/lists.md"
n=1
tanggalWaktu=$(date +"%d-%m-%Y %H:%M:%S")
mkdir -p ./logs
while read line; do
fileName=$(awk -F'[/ ]' '{print $2}' $line)
echo "file -> $fileName"
done < $filename
Output:
awk: can't open file ./SolutionController.php
source line number
Please help me
Using awk :
awk -F'[/ ]' '{print $2}' string.txt
Using gawk:
awk '{print gensub(/\.\/(.*) (.*)/,"\\1","g")}' string.txt
Test Results:
$ cat string.txt
./SolutionController.php core/app/Http/Controllers/Admin/SolutionController.php
./ContentController.php core/app/Http/Controllers/Frontpage/ContentController.php
./country-flag vendor/country-flag
$ awk -F'[/ ]' '{print $2}' string.txt
SolutionController.php
ContentController.php
country-flag
$ awk '{print gensub(/\.\/(.*) (.*)/,"\\1","g")}' string.txt
SolutionController.php
ContentController.php
country-flag
You can do it
echo "./SolutionController.php core/app/Http/Controllers/Admin/SolutionController.php" | sed -r 's/\.\/(.*) .*/\1/'
If you stored it in the file.
sed -r 's/\.\/(.*) .*/\1/' strings.txt
I found some ways to pass external shell variables to an awk script, but I'm confused about ' and ".
First, I tried with a shell script:
$ v=123test
$ echo $v
123test
$ echo "$v"
123test
Then tried awk:
$ awk 'BEGIN{print "'$v'"}'
$ 123test
$ awk 'BEGIN{print '"$v"'}'
$ 123
Why is the difference?
Lastly I tried this:
$ awk 'BEGIN{print " '$v' "}'
$ 123test
$ awk 'BEGIN{print ' "$v" '}'
awk: cmd. line:1: BEGIN{print
awk: cmd. line:1: ^ unexpected newline or end of string
I'm confused about this.
#Getting shell variables into awk
may be done in several ways. Some are better than others. This should cover most of them. If you have a comment, please leave below. v1.5
Using -v (The best way, most portable)
Use the -v option: (P.S. use a space after -v or it will be less portable. E.g., awk -v var= not awk -vvar=)
variable="line one\nline two"
awk -v var="$variable" 'BEGIN {print var}'
line one
line two
This should be compatible with most awk, and the variable is available in the BEGIN block as well:
If you have multiple variables:
awk -v a="$var1" -v b="$var2" 'BEGIN {print a,b}'
Warning. As Ed Morton writes, escape sequences will be interpreted so \t becomes a real tab and not \t if that is what you search for. Can be solved by using ENVIRON[] or access it via ARGV[]
PS If you have vertical bar or other regexp meta characters as separator like |?( etc, they must be double escaped. Example 3 vertical bars ||| becomes -F'\\|\\|\\|'. You can also use -F"[|][|][|]".
Example on getting data from a program/function inn to awk (here date is used)
awk -v time="$(date +"%F %H:%M" -d '-1 minute')" 'BEGIN {print time}'
Example of testing the contents of a shell variable as a regexp:
awk -v var="$variable" '$0 ~ var{print "found it"}'
Variable after code block
Here we get the variable after the awk code. This will work fine as long as you do not need the variable in the BEGIN block:
variable="line one\nline two"
echo "input data" | awk '{print var}' var="${variable}"
or
awk '{print var}' var="${variable}" file
Adding multiple variables:
awk '{print a,b,$0}' a="$var1" b="$var2" file
In this way we can also set different Field Separator FS for each file.
awk 'some code' FS=',' file1.txt FS=';' file2.ext
Variable after the code block will not work for the BEGIN block:
echo "input data" | awk 'BEGIN {print var}' var="${variable}"
Here-string
Variable can also be added to awk using a here-string from shells that support them (including Bash):
awk '{print $0}' <<< "$variable"
test
This is the same as:
printf '%s' "$variable" | awk '{print $0}'
P.S. this treats the variable as a file input.
ENVIRON input
As TrueY writes, you can use the ENVIRON to print Environment Variables.
Setting a variable before running AWK, you can print it out like this:
X=MyVar
awk 'BEGIN{print ENVIRON["X"],ENVIRON["SHELL"]}'
MyVar /bin/bash
ARGV input
As Steven Penny writes, you can use ARGV to get the data into awk:
v="my data"
awk 'BEGIN {print ARGV[1]}' "$v"
my data
To get the data into the code itself, not just the BEGIN:
v="my data"
echo "test" | awk 'BEGIN{var=ARGV[1];ARGV[1]=""} {print var, $0}' "$v"
my data test
Variable within the code: USE WITH CAUTION
You can use a variable within the awk code, but it's messy and hard to read, and as Charles Duffy points out, this version may also be a victim of code injection. If someone adds bad stuff to the variable, it will be executed as part of the awk code.
This works by extracting the variable within the code, so it becomes a part of it.
If you want to make an awk that changes dynamically with use of variables, you can do it this way, but DO NOT use it for normal variables.
variable="line one\nline two"
awk 'BEGIN {print "'"$variable"'"}'
line one
line two
Here is an example of code injection:
variable='line one\nline two" ; for (i=1;i<=1000;++i) print i"'
awk 'BEGIN {print "'"$variable"'"}'
line one
line two
1
2
3
.
.
1000
You can add lots of commands to awk this way. Even make it crash with non valid commands.
One valid use of this approach, though, is when you want to pass a symbol to awk to be applied to some input, e.g. a simple calculator:
$ calc() { awk -v x="$1" -v z="$3" 'BEGIN{ print x '"$2"' z }'; }
$ calc 2.7 '+' 3.4
6.1
$ calc 2.7 '*' 3.4
9.18
There is no way to do that using an awk variable populated with the value of a shell variable, you NEED the shell variable to expand to become part of the text of the awk script before awk interprets it. (see comment below by Ed M.)
Extra info:
Use of double quote
It's always good to double quote variable "$variable"
If not, multiple lines will be added as a long single line.
Example:
var="Line one
This is line two"
echo $var
Line one This is line two
echo "$var"
Line one
This is line two
Other errors you can get without double quote:
variable="line one\nline two"
awk -v var=$variable 'BEGIN {print var}'
awk: cmd. line:1: one\nline
awk: cmd. line:1: ^ backslash not last character on line
awk: cmd. line:1: one\nline
awk: cmd. line:1: ^ syntax error
And with single quote, it does not expand the value of the variable:
awk -v var='$variable' 'BEGIN {print var}'
$variable
More info about AWK and variables
Read this faq.
It seems that the good-old ENVIRON awk built-in hash is not mentioned at all. An example of its usage:
$ X=Solaris awk 'BEGIN{print ENVIRON["X"], ENVIRON["TERM"]}'
Solaris rxvt
You could pass in the command-line option -v with a variable name (v) and a value (=) of the environment variable ("${v}"):
% awk -vv="${v}" 'BEGIN { print v }'
123test
Or to make it clearer (with far fewer vs):
% environment_variable=123test
% awk -vawk_variable="${environment_variable}" 'BEGIN { print awk_variable }'
123test
You can utilize ARGV:
v=123test
awk 'BEGIN {print ARGV[1]}' "$v"
Note that if you are going to continue into the body, you will need to adjust
ARGC:
awk 'BEGIN {ARGC--} {print ARGV[2], $0}' file "$v"
I just changed #Jotne's answer for "for loop".
for i in `seq 11 20`; do host myserver-$i | awk -v i="$i" '{print "myserver-"i" " $4}'; done
I had to insert date at the beginning of the lines of a log file and it's done like below:
DATE=$(date +"%Y-%m-%d")
awk '{ print "'"$DATE"'", $0; }' /path_to_log_file/log_file.log
It can be redirect to another file to save
Pro Tip
It could come handy to create a function that handles this so you dont have to type everything every time. Using the selected solution we get...
awk_switch_columns() {
cat < /dev/stdin | awk -v a="$1" -v b="$2" " { t = \$a; \$a = \$b; \$b = t; print; } "
}
And use it as...
echo 'a b c d' | awk_switch_columns 2 4
Output:
a d c b
I want to get the filename from a long string in shell script.After reading some example from likegeeks.com,I write a simple solution:
#/bin/bash
cdnurl="http://download.example.com.cn/download/product/vpn/rules/vpn_patch_20190218162130_sign.pkg?wsSecret=9cadeddedfr7bb85a20a064510cd3f353&wsABSTime=5c6ea1e7"
echo ${cndurl}
url=`echo ${cdnurl} | awk -F'/' '{ print $NF }'`
result=`echo ${url} | awk -F '?' '{ print $1}'`
echo ${url}
echo ${result}
I just want to get vpn_patch_20190218162130_sign.pkg,and the it does.I wonder is there any smart ways (may be one line).
If behind pkg it's not ?,how to use pkg to get the filename,I am not sure if always ? after pkg,but the filename always be *.pkg.
You can try : this is more robust as compare to second awk command:
echo "$cdnurl"|awk -v FS='/' '{gsub(/?.*/,"",$NF);print $NF}'
vpn_patch_20190218162130_sign.pkg
#less robust
echo "$cdnurl"|awk -vFS=[?/] '{print $(NF-1)}'
You should use sed :
sed -r 's|.*/(.*.pkg).*|\1|g'
I have the following grep and gawk line running in windows
grep ItemDischarged D:\systems\CmcComRouting.log | gawk -v OFS=, "{print $8}" | cut -d ">" -f 1 | uniq -c | gawk -v OFS=, "{print $1,$2}" > d:\03TotalItems.log
the output is as follows
59523,ItemDischargedTlg
What I want to do is add "Lower" to the end of "ItemDischargedTlg" but cannot figure out how to do it, I have tried
{print $1,$2"Lower"}
but it prints nothing.
Thanks
This might do the trick:
gawk -v OFS=, '{$2=$2"Lower";print $1,$2}'
When trying to concatenate strings and commas you should be careful. Commas and concatenation as argument of a print instruction don't go well together.
If on windows, be careful with " and '.
how to pass and compare an external variable in awk command? is it also dependent on unix shell that we are using
I am trying to do :
mgrid=`echo $file1 | awk -F'|' '{ print $40}' `
echo $mgrid
var=`/usr/bin/more $HOME/pwd_date_chk/file2.txt | awk -F'|' ' -v search="$mgrid" '{ $41 ~ search print $15}'`
echo $var
awk can read the input from file. No need to use more. You can try this,
mgrid=`echo $file1 | awk -F'|' '{ print $40}' `
echo $mgrid
var=`awk -F'|' -v search="$mgrid" '$41 ~ search {print $15}' $HOME/pwd_date_chk/file2.txt`
echo $var