I have written a small script that loops through directories (starting from a given argument directory) and prompts directories that have an xml file inside. Here is my code :
#! /bin/bash
process()
{
LIST_ENTRIES=$(find $1 -mindepth 1 -maxdepth 1)
regex="\.xml"
if [[ $LIST_ENTRIES =~ $regex ]]; then
echo "$1"
fi
# Process found entries
while read -r line
do
if [[ -d $line ]]; then
process $line
fi
done <<< "$LIST_ENTRIES"
}
process $1
This code works fine. However, if I change the regex to \.xml$ to indicate that it should match at the end of the line, the result is different, and I do not get all the right directories.
Is there something wrong with this ?
Your variable LIST_ENTRIES may not have .xml as the last entry.
To validate, try echo $LIST_ENTRIES.
To overcome this, use for around your if:
process()
{
LIST_ENTRIES=$(find $1 -mindepth 1 -maxdepth 1)
regex="\.xml$"
for each in $LIST_ENTRIES; do
if [[ $each =~ $regex ]]; then
echo "$1"
fi
done
# Process found entries
while read -r line
do
if [[ -d $line ]]; then
process $line
fi
done <<< "$LIST_ENTRIES"
}
process $1
Related
I have a file a.txt contains a string like:
Axxx-Bxxxx
Rules for checking if it is valid or not include:
length is 10 characters.
x here is digits only.
Then, I try to check with:
#!/bin/bash
exp_len=10;
file=a.txt;
msg="checking string";
tmp="File not exist";
echo $msg;
if[ -f $file];then
tmp=$(cat $file);
if[[${#tmp} != $exp_len ]];then
msg="invalid length";
elif [[ $tmp =~ ^[A[0-9]{3}-B[0-9]{4}]$]];then
msg="valid";
else
msg="invalid";
fi
else
msg="file not exist";
fi
echo $msg;
But in valid case it doesn't work...
Is there someone help to correct me?
Thanks :)
Other than the regex fix, your code can be refactored as well, moreover there are syntax issues as well. Consider this code:
file="a.txt"
msg="checking string"
tmp="File not exist"
echo "$msg"
if [[ -f $file ]]; then
s="$(<$file)"
if [[ $s =~ ^A[0-9]{3}-B[0-9]{4}$ ]]; then
msg="valid"
else
msg="invalid"
fi
else
msg="file not exist"
fi
echo "$msg"
Changes are:
Remove unnecessary cat
Use [[ ... ]] when using bash
Spaces inside [[ ... ]] are required (your code was missing them)
There is no need to check length of 10 as regex will make sure that part as well
As mentioned in comments earlier correct regex should be ^A[0-9]{3}-B[0-9]{4}$ or ^A[[:digit:]]{3}-B[[:digit:]]{4}$
Note that a regex like ^[A[0-9]{3}-B[0-9]{4}]$ matches
^ - start of string
[A[0-9]{3} - three occurrences of A, [ or a digit
-B - a -B string
[0-9]{4} - four digits
] - a ] char
$ - end of string.
So, it matches strings like [A[-B1234], [[[-B1939], etc.
Your regex checking line must look like
if [[ $tmp =~ ^A[0-9]{3}-B[0-9]{4}$ ]];then
See the online demo:
#!/bin/bash
tmp="A123-B1234";
if [[ $tmp =~ ^A[0-9]{3}-B[0-9]{4}$ ]];then
msg="valid";
else
msg="invalid";
fi
echo $msg;
Output:
valid
Using just grep might be easier:
$ echo A123-B1234 > valid.txt
$ echo 123 > invalid.txt
$ grep -Pq 'A\d{3}-B\d{4}' valid.txt && echo valid || echo invalid
valid
$ grep -Pq 'A\d{3}-B\d{4}' invalid.txt && echo valid || echo invalid
invalid
With your shown samples and attempts, please try following code also.
#!/bin/bash
exp_len=10;
file=a.txt;
msg="checking string";
tmp="File not exist";
if [[ -f "$file" ]]
then
echo "File named $file is existing.."
awk '/^A[0-9]{3}-B[0-9]{4}$/{print "valid";next} {print "invalid"}' "$file"
else
echo "Please do check File named $file is not existing, exiting from script now..."
exit 1;
fi
OR In case you want to check if line in your Input_file should be 10 characters long(by seeing OP's attempted code's exp_len shell variable) then try following code, where an additional condition is also added in awk code.
#!/bin/bash
exp_len=10;
file=a.txt;
msg="checking string";
tmp="File not exist";
if [[ -f "$file" ]]
then
echo "File named $file is existing.."
awk -v len="$exp_len" 'length($0) == len && /^A[0-9]{3}-B[0-9]{4}$/{print "valid";next} {print "invalid"}' "$file"
else
echo "Please do check File named $file is not existing, exiting from script now..."
exit 1;
fi
NOTE: I am using here -f flag to test if file is existing or not, you can change it to -s eg: -s "$file" in case you want to check file is present and is of NOT NULL size.
I have a file (file.txt) that contains some text like:
000000000+000+0+00
000000001+000+0+00
000000002+000+0+00
and I am trying to check each line to make sure that it follows the format:
character*9, "+", character*3, "+", etc
so far I have:
#!/bin/ksh
file=file.txt
line_number=1
for line in $(cat $file)
do
if [[ "$line" != "[[.]]{9}+[[.]]{3}+[[.]]{1}+[[.]]{2} ]" ]]
then
echo "Invalid number ($line) check line $line_number"
exit 1
fi
let "line_number++"
done
however this does not evaluate correctly, no matter what I put in the lines the program terminates.
When you want line numbers of the mismatches, you can use grep -vn. Be careful with writing a correct regular expression, and you will have
grep -Evn "^.{9}[+].{3}[+].[+].{2}$" file.txt
This is not in the layout that you want, so change the layout with sed:
grep -Evn "^.{9}[+].{3}[+].[+].{2}$" file.txt |
sed -r 's/([^:]*):(.*)/Invalid number (\2) check line number \1./'
EDIT:
I changed .{1} into ..
The sed is also over the top. When you need spme explanation, you can start with echo "Linenr:Invalid line"
I'm having funny results putting the regex in the condition directly:
$ line='000000000+000+0+00'
$ [[ $line =~ ^.{9}\+.{3}\+.\+..$ ]] && echo ok
ksh: syntax error: `~(E)^.{9}\+.{3}\+.\+..$ ]] && echo ok
' unexpected
But if I save the regex in a variable:
$ re="^.{9}\+.{3}\+.\+..$"
$ [[ $line =~ $re ]] && echo ok
ok
So you can do
#!/bin/ksh
file=file.txt
line_number=1
re="^.{9}\+.{3}\+.\+..$"
while IFS= read -r line; do
if [[ ! $line =~ $re ]]; then
echo "Invalid number ($line) check line $line_number"
exit 1
fi
let "line_number++"
done < "$file"
You can also use a plain glob pattern:
if [[ $line != ?????????+???+?+?? ]]; then echo error; fi
ksh glob patterns have some regex-like syntax. If there's an optional space in there, you can handle that with the ?(sub-pattern) syntax
pattern="?????????+???+?( )?+??"
line1="000000000+000+0+00"
line2="000000000+000+ 0+00"
[[ $line1 == $pattern ]] && echo match || echo no match # => match
[[ $line2 == $pattern ]] && echo match || echo no match # => match
Read the "File Name Generation" section of the ksh man page.
Your regex looks bad - using sites like https://regex101.com/ is very helpful. From your description, I suspect it should look more like one of these;
^.{9}\+.{3}\+.{1}\+.{2}$
^[^\+]{9}\+[^\+]{3}\+[^\+]{1}\+[^\+]{2}$
^[0-9]{9}\+[0-9]{3}\+[0-9]{1}\+[0-9]{2}$
From the ksh manpage section on [[ - you would probably want to be using =~.
string =~ ere
True if string matches the pattern ~(E)ere where ere is an extended regular expression.
Note: As far as I know, ksh regex doesn't follow the normal syntax
You may have better luck with using grep:
# X="000000000+000+0+00"
# grep -qE "^[^\+]{9}\+[^\+]{3}\+[^\+]{1}\+[^\+]{2}$" <<<"${X}" && echo true
true
Or:
if grep -qE "^[^\+]{9}\+[^\+]{3}\+[^\+]{1}\+[^\+]{2}$" <<<"${line}"
then
exit 1
fi
You may also prefer to use a construct like below for handling files:
while read line; do
echo "${line}";
done < "${file}"
In a list of files:
javascript-custom-rules-plugin-1.0-SNAPSHOT.jar
README.txt
sonar-build-breaker-plugin-2.0.jar
sonar-javascript-plugin-2.11.jar
tmo-custom-rules-1.0.jar
I am attempting to match these filenames by regex.
My Script
#!/usr/bin/env bash
install_location=/usr/local/sonar/extensions/plugins
for f in $(ls -1 $install_location)
do
# remove any previous versions of this plugin
if [[ "$f" =~ ".*tmo-custom-rules-(.+)\.jar" ]]
then
echo "found $f. will remove"
else
echo "$f doesn't match"
fi
done
I've tried if [[ "$f" =~ ".*tmo-custom-rules-(.+)\.jar" ]] and if [[ "$f" == *"tmo-custom-rules" ]] to no avail.
I'm getting
javascript-custom-rules-plugin-1.0-SNAPSHOT.jar doesn't match
README.txt doesn't match
sonar-build-breaker-plugin-2.0.jar doesn't match
sonar-javascript-plugin-2.11.jar doesn't match
tmo-custom-rules-1.0.jar doesn't match
when I expect found tmo-custom-rules-1.0.jar. will remove
I've run my regular expression through many regular expression testers with the data above, and they all return the correct matches, but I can't get it to work here in my script.
How can I loop through, and check to see if any files matches this regular expression?
In BASH regex must be unquoted so this should work:
[[ $f =~ .*tmo-custom-rules-(.+)\.jar ]]
Or better:
re=".*tmo-custom-rules-(.+)\.jar"
[[ $f =~ $re ]]
However you don't even need regex and can use shell glob matching:
#!/usr/bin/env bash
install_location=/usr/local/sonar/extensions/plugins
for f in "$install_location"/*
do
# remove any previous versions of this plugin
if [[ $f == *tmo-custom-rules-*.jar ]]
then
echo "found $f. will remove"
else
echo "$f doesn't match"
fi
done
Note that you can avoid using output of ls which is not always fit for scripting.
You can do this with expr using the colon operator:
if expr "$f" : '.*tmo-custom-rules-.*\.jar' > /dev/null; then
echo matches
fi
Note that the regular expressions in this context are assumed to be anchored to the start of the line.
I have a value in a variable that may be absolute or relative url, and I need to check which one it is.
I have found that there's a =~ operator in [[, but I can't get it to work. What am I doing wrong?
url="http://test"
if [[ "$url" =~ "^http://" ]];
then echo "absolute.";
fi;
You need to use regex without quote:
url="http://test"
if [[ "$url" =~ ^http:// ]]; then
echo "absolute."
fi
This outputs `absolute. as regex needs to be without quote in newer BASH (after BASH v3.1)
Or avoid regex and use glob matching:
if [[ "$url" == "http://"* ]]; then
echo "absolute."
fi
#!/bin/bash
# This file will fix the cygwin vs linux paths and load programmer's notepad under windows.
# mail : <sandundhammikaperera#gmail.com>
# invokes the GNU GPL, all rights are granted.
# check first parameter is non empty.
# if empty then give a error message and exit.
file=${1:?"Usage: pn filename"};
if [[ "$file" == /*/* ]] ;then
#if long directory name.
# :FAILTHROUGH:
echo "$0: Executing pn.exe $file"
else
file="$(pwd)/$file";
fi
#check whether the filename starts with / if so replace it with appropriate prefix #
prefix="C:/cygwin/";
#check for the partterns starting with "/" #
echo $var | grep "^/*$"
if [[ "$?" -eq "0" ]] ;then
# check again whether parttern starts with /cygdrive/[a-z]/ parttern #
if [[ $file == /cygdrive/[a-z]/* ]] ; then
file=${file#/cygdrive/[a-z]/};
file="C:/"$file;
else
file="$prefix""$file";
fi
fi
#check for the appropriate file permissions #
# :TODO:
echo $file
exec "/cygdrive/c/Program Files (x86)/Programmer's Notepad/pn.exe" $file
as I in my program which convert path names between cygwin and windows and load
the pn.exe [ programmer's notepad in windows]. So my questions are,
There are built in regex expression for the "[[" or 'test' operator. (as well as
I used them in my above program). But why they don't work in here if I change,
echo $var | grep "^/*$"
if [[ "$?" -eq "0" ]] ;then
to this,
if [[ "$file" == ^/*$ ]] ;then
What is the reason for that? Is there any workaround?
I have already tried the second method [[ "$file" == ^/*$ ]] but it didn't work.
then , simple googling brought to me here: http://unix.com/shell-programming
How to find all the documentation about [[ operator or 'test' command? I have used
man test but :(. Which document specifies it's limitations on regex usage if there so.
First, grep "^/*$" will only match paths containing only slashes, like "/", "///", "////". You can use grep "^/" to match paths starting with a slash. If you want to use bash regexes:
var="/some"
#echo $var | grep "^/"
if [[ "$var" =~ ^/ ]] ;then
echo "yes"
fi