Let's say I have some text in a variable called $1. Now I want to check if that $1 contains a certain string. If it contains a certain string I want to print a message. The printing is not the problem, the problem is the check. Any ideas how to do that?
The easiest way in my opinion is this :
set YourString=This is a test
If NOT "%YourString%"=="%YourString:test=%" (
echo Yes
) else (
echo No
)
Basiclly the string after ':' is the string you are looking for and you are using not infront of the if because %string:*% will remove the * from the string making them not equal.
The SET search and replace trick works in many cases, but it does not support case sensitive or regular expression searches.
If you need a case sensitive search or limited regular expression support, you can use FINDSTR.
To avoid complications of escaping special characters, it is best if the search string is in a variable and both search and target are accessed via delayed expansion.
You can pipe $1 into the FINDSTR command with the ECHO command. Use ECHO( in case $1 is undefined, and be careful not to add extra spaces. ECHO !$1! will echo ECHO is off. (or on) if $1 is undefined, whereas ECHO(!$1! will echo a blank line if undefined.
FINDSTR will echo $1 if it finds the search string - you don't want that so you redirect output to nul. FINDSTR sets ERRORLEVEL to 0 if the search string is found, and 1 if it is not found. That is what is used to check if the string was found. The && and || is a convenient syntax to use to test for match (ERRORLEVEL 0) or no match (ERRORLEVEL not 0)
The regular expression support is rudimentary, but still useful.
See FINDSTR /? for more info.
This regular expression example will search $1 for "BEGIN" at start of string, "MID" anywhere in middle, and "END" at end. The search is case sensitive by default.
set "search=^BEGIN.*MID.*END$"
setlocal enableDelayedExpansion
echo(!$1!|findstr /r /c:"!search!" >nul && (
echo FOUND
rem any commands can go here
) || (
echo NOT FOUND
rem any commands can go here
)
As far as I know cmd.exe has no built-in function which answers your question directly. But it does support replace operation. So the trick is: in your $1 replace the substring you need to test the presence of with an empty string, then check if $1 has changed. If it has then it did contain the substring (otherwise the replace operation would have had nothing to replace in the first place!). See the code below:
set longString=the variable contating (or not containing) some text
#rem replace xxxxxx with the string you are looking for
set tempStr=%longString:xxxxxx=%
if "%longString%"=="%tempStr%" goto notFound
echo Substring found!
goto end
:notFound
echo Substring not found
:end
Related
I want to isolate a specific string from a text provided in a variable, using batch, but it doesn't seem to work as intended. I may do the regexp wrong, or maybe I misunderstood the way "findstr" works.
Te specific string that I need to isolate is a GUID (which has a standard format of alphanumeric characters, arranged in groups of characters separated by a "-", like this: 8-4-4-4-12)
#echo off
setlocal enabledelayedexpansion
SET str="This is a string that has a long uuid: (UUID: 359f975d-2649-4e20-b7c0-b452aaaca4b2)"
SET rx=[a-zA-Z0-9]{8}-[a-zA-Z0-9]{4}-[a-zA-Z0-9]{4}-[a-zA-Z0-9]{4}-[a-zA-Z0-9]{12}
FOR %%u IN ('FINDSTR /r "!rx!" "!str!"') DO ECHO %%u
endlocal
Basically, what I need is to store the GUID in a separate variable, so I can use it later on. If that can be achieved in a different manner, I'm happy to learn!
Thanks!
#ECHO Off
SETLOCAL
SET "str=This is a string that has a long uuid: (UUID: 359f975d-2649-4e20-b7c0-b452aaaca4b2)"
:: Theoretical
SET "hn=[a-f0-9]"
SET "hn4=%hn%%hn%%hn%%hn%"
SET "hn8=%hn4%%hn4%"
SET "wrx=%hn8%-%hn4%-%hn4%-%hn4%-%hn8%%hn4%"
:again
IF NOT DEFINED str ECHO notfound&GOTO done
ECHO %str%|FINDSTR /b /r /i "%wrx%">NUL
IF ERRORLEVEL 1 (
REM did not find string
SET "str=%str:~1%"
GOTO again
)
SET "str=%str:~0,36%"
ECHO found "%str%"
:done
:: BFI method
SET "str=This is a string that has a long uuid: (UUID: 359f975d-2649-4e20-b7c0-b452aaaca4b2)"
SET "hn=[a-f0-9]"
SET "hn4=%hn%%hn%%hn%%hn%"
SET "hn8=%hn4%%hn4%"
:bfiagain
IF NOT DEFINED str ECHO notfound&GOTO donebfi
:: "regex" using brute-force and ignorance
ECHO %str:~0,9%|FINDSTR /b /i /r "%hn8%-">NUL
IF ERRORLEVEL 1 GOTO bfino
ECHO %str:~9,5%|FINDSTR /b /i /r "%hn4%-">NUL
IF ERRORLEVEL 1 GOTO bfino
ECHO %str:~14,10%|FINDSTR /b /i /r "%hn4%-%hn4%-">NUL
IF ERRORLEVEL 1 GOTO bfino
ECHO %str:~24,12%|FINDSTR /b /i /r "%hn4%%hn8%">NUL
:bfino
IF ERRORLEVEL 1 (
SET "str=%str:~1%"
GOTO bfiagain
)
SET "str=%str:~0,36%"
ECHO found "%str%"
:donebfi
GOTO :EOF
Well, not so squeezy...
Fundamentally, findstr implements a very small subset of regex. It's intended to locate a character-string in a file.
Theoretically, you could string [a-f0-9] together the requisite number of times and add in the - separators for use as the "regex", then see whether the subject string /b (begins) with such a pattern; lop off the start character if not and repeat until found or subject-string is empty.
Notes here: I believe GUID uses HEX digits only, not alphanumerics. findstr supports /i to have the comparison made case-insensitively (which shortens the individual "character-match" string). Yes - I know ^ can be used in a regex (even one from Uncle Bill's little programmers' toolset) but I prefer /b.
The only small problem with this is that it yielded an out of memory error...
So, feed it small chunks at a time, and it appears happy...
I've done no further testing, and predict stormy weather if your text-string contains characters which cmd regards as specials - the usual suspects like redirectors, % and rabbit's ears.
I am writing a batch script that takes in various arguments before starting another process. In the example below I am checking the case where the first argument was 1, and the second argument is in the form of "any number of digits 0-9, followed by the letter k, m, or g" (I am specifying the amount of memory the process should start with i.e. 10g = 10 Gb memory).
If I just want a number this will suffice:
IF [%1] EQU [1] ECHO %2|findstr /r "[^0-9]" > nul
IF [%1] EQU [1] IF errorlevel 1 echo starting test number %1 with %2 of memory
What I thought would be an obvious segway to add the letters k, m, or g led me to this (I've tried with and without the '*'):
IF [%1] EQU [1] ECHO %2|findstr /r "[^0-9]*[kmg]" > nul
IF [%1] EQU [1] IF errorlevel 1 echo starting test number %1 with %2 of memory
However I have been unable to match any string to this FINDSTR pattern. Basically I am looking for a FINDSTR that matches [0-9][0-9]*[kmg]. I am fairly certain I am close but am having trouble working out the correct syntax.
Even the first code you posted does not work. [^0-9] looks for any non-digit. I think you wanted ^[0-9], which means any string that starts with a digit. Your logic is also wrong: FINDSTR sets errorlevel to 0 if found, and 1 if not found. I prefer to use the conditional && and || operators to test the result instead of IF.
I recommend the following for what you are attempting. I've thrown in the /I switch to make it case insensitive. I add the /X switch to prevent the string from matching if there are extra characters before or after the number with suffix.
#echo off
if "%~1" equ "1" echo(%~2|findstr /rix "[0-9][0-9]*[kgm]" >nul && (
echo starting test number %~1 with %~2 of memory
)
Unfortunately, FINDSTR does not support the ? meta-character. So the solution is slightly more complicated if the suffix is optional (if you want to support bytes, kilobytes, megabytes, and gigabytes). You would need to search for either of 2 strings, one with the suffix, and one without. FINDSTR breaks the search string into multiple search strings at spaces.
#echo off
if "%~1" equ "1" echo(%~2|findstr /rix "[0-9][0-9]*[kgm] [0-9][0-9]*" >nul && (
echo starting test number %~1 with %~2 of memory
)
I am very new to regex, therefore I do imagine this is quite a simple question to answer and must have been asked several times already, but unfortunly I can't find any of those answers.
Given a directory, I need the list of all of its subdirectories whose names respect the pattern "nw=[number].a=[number]", and for every directory I need to retrieve those numbers and do a few things based on those. Some of these directories are nw=82.a=40, nw=100.a=9, ecc.
My guess to accomplish this would be
#! /bin/bash
cd $mydir
for dir in `ls | grep nw=[:digit:]+.a=[:digit:]`: do
retrieve the numbers
a few things
done
Why doesn't it work, and how could I retrieve the numbers?
Thank you in advance,
Ferdinando
Some corrections on your grep command:
grep -E 'nw=[[:digit:]]+\.a=[[:digit:]]+'
Use the "-E" flag so you can use an extended regex, which includes the '+' operator, for example.
Use double square brackets
Escape the period, otherwise it will be used as an operator to match any character
A final '+' was missing from the end, not entirely necessary since grep will match more general cases, but it probably represents better your path names
It is probably good practice to place your regex between quotes (in this case, single quotes will do)
Hope this helps =)
perl -e '#a=`ls`;m/nw=(\d+)\.a=(\d+)(?{print"$1\t$2\n"})/ for#a'
Enjoy.
Call the terminal's ls command and store the list in the array #a.
#a=`ls`;
looking for match
m/
nw=(digits that I capture in $1).a=(digits that I capture in $2)
nw=(\d+)\.a=(\d+)
start evaluation of code from within a pattern
(?{
print first number,tab, second number, newline
print"$1\t$2\n"})
end matching pattern group
/
perform this match attempt with embedded code on each filename (with newlines still appended) in array #a
for#a
Yes, that was cryptic.
Don't parse ls. Use find instead:
find . -maxdepth 1 -type d -regex '.*nw=[0-9]+\.a=[0-9]+.*' | while IFS= read -r dir
do
echo "Found directory: $dir"
if [[ "$dir" =~ nw=([0-9]+)\.a=([0-9]+) ]]
then
echo "numbers are ${BASH_REMATCH[1]} and ${BASH_REMATCH[2]}"
fi
done
Consider the following:
var="text more text and yet more text"
echo $var | egrep "yet more (text)"
It should be possible to get the result of the regex as the string: text
However, I don't see any way to do this in bash with grep or its siblings at the moment.
In perl, php or similar regex engines:
$output = preg_match('/yet more (text)/', 'text more text yet more text');
$output[1] == "text";
Edit: To elaborate why I can't just multiple-regex, in the end I will have a regex with multiple of these (Pictured below) so I need to be able to get all of them. This also eliminates the option of using lookahead/lookbehind (As they are all variable length)
egrep -i "([0-9]+) +$USER +([0-9]+).+?(/tmp/Flash[0-9a-z]+) "
Example input as requested, straight from lsof (Replace $USER with "j" for this input data):
npviewer. 17875 j 11u REG 8,8 59737848 524264 /tmp/FlashXXu8pvMg (deleted)
npviewer. 17875 j 17u REG 8,8 16037387 524273 /tmp/FlashXXIBH29F (deleted)
The end goal is to cp /proc/$var1/fd/$var2 ~/$var3 for every line, which ends up "Downloading" flash files (Flash used to store in /tmp but they drm'd it up)
So far I've got:
#!/bin/bash
regex="([0-9]+) +j +([0-9]+).+?/tmp/(Flash[0-9a-zA-Z]+)"
echo "npviewer. 17875 j 11u REG 8,8 59737848 524264 /tmp/FlashXXYOvS8S (deleted)" |
sed -r -n -e " s%^.*?$regex.*?\$%\1 \2 \3%p " |
while read -a array
do
echo /proc/${array[0]}/fd/${array[1]} ~/${array[2]}
done
It cuts off the first digits of the first value to return, and I'm not familiar enough with sed to see what's wrong.
End result for downloading flash 10.2+ videos (Including, perhaps, encrypted ones):
#!/bin/bash
lsof | grep "/tmp/Flash" | sed -r -n -e " s%^.+? ([0-9]+) +$USER +([0-9]+).+?/tmp/(Flash[0-9a-zA-Z]+).*?\$%\1 \2 \3%p " |
while read -a array
do
cp /proc/${array[0]}/fd/${array[1]} ~/${array[2]}
done
Edit: look at my other answer for a simpler bash-only solution.
So, here the solution using sed to fetch the right groups and split them up. You later still have to use bash to read them. (And in this way it only works if the groups themselves do not contain any spaces - otherwise we had to use another divider character and patch read by setting $IFS to this value.)
#!/bin/bash
USER=j
regex=" ([0-9]+) +$USER +([0-9]+).+(/tmp/Flash[0-9a-zA-Z]+) "
sed -r -n -e " s%^.*$regex.*\$%\1 \2 \3%p " |
while read -a array
do
cp /proc/${array[0]}/fd/${array[1]} ~/${array[2]}
done
Note that I had to adapt your last regex group to allow uppercase letters, and added a space at the beginning to be sure to capture the whole block of numbers. Alternatively here a \b (word limit) would have worked, too.
Ah, I forget mentioning that you should pipe the text to this script, like this:
./grep-result.sh < grep-result-test.txt
(provided your files are named like this). Instead you can add a < grep-result-test after the sed call (before the |), or prepend the line with cat grep-result-test.txt |.
How does it work?
sed -r -n calls sed in extended-regexp-mode, and without printing anything automatically.
-e " s%^.*$regex.*\$%\1 \2 \3%p " gives the sed program, which consists of a single s command.
I'm using % instead of the normal / as parameter separator, since / appears inside the regex and I don't want to escape it.
The regex to search is prefixed by ^.* and suffixed by .*$ to grab the whole line (and avoid printing parts of the rest of the line).
Note that this .* grabs greedy, so we have to insert a space into our regexp to avoid it grabbing the start of the first digit group too.
The replacement text contains of the three parenthesed groups, separated by spaces.
the p flag at the end of the command says to print out the pattern space after replacement. Since we grabbed the whole line, the pattern space consists of only the replacement text.
So, the output of sed for your example input is this:
5 11 /tmp/FlashXXu8pvMg
5 17 /tmp/FlashXXIBH29F
This is much more friendly for reuse, obviously.
Now we pipe this output as input to the while loop.
read -a array reads a line from standard input (which is the output from sed, due to our pipe), splits it into words (at spaces, tabs and newlines), and puts the words into an array variable.
We could also have written read var1 var2 var3 instead (preferably using better variable names), then the first two words would be put to $var1 and $var2, with $var3 getting the rest.
If read succeeded reading a line (i.e. not end-of-file), the body of the loop is executed:
${array[0]} is expanded to the first element of the array and similarly.
When the input ends, the loop ends, too.
This isn't possible using grep or another tool called from a shell prompt/script because a child process can't modify the environment of its parent process. If you're using bash 3.0 or better, then you can use in-process regular expressions. The syntax is perl-ish (=~) and the match groups are available via $BASH_REMATCH[x], where x is the match group.
After creating my sed-solution, I also wanted to try the pure-bash approach suggested by Mark. It works quite fine, for me.
#!/bin/bash
USER=j
regex=" ([0-9]+) +$USER +([0-9]+).+(/tmp/Flash[0-9a-zA-Z]+) "
while read
do
if [[ $REPLY =~ $regex ]]
then
echo cp /proc/${BASH_REMATCH[1]}/fd/${BASH_REMATCH[2]} ~/${BASH_REMATCH[3]}
fi
done
(If you upvote this, you should think about also upvoting Marks answer, since it is essentially his idea.)
The same as before: pipe the text to be filtered to this script.
How does it work?
As said by Mark, the [[ ... ]] special conditional construct supports the binary operator =~, which interprets his right operand (after parameter expansion) as a extended regular expression (just as we want), and matches the left operand against this. (We have again added a space at front to avoid matching only the last digit.)
When the regex matches, the [[ ... ]] returns 0 (= true), and also puts the parts matched by the individual groups (and the whole expression) into the array variable BASH_REMATCH.
Thus, when the regex matches, we enter the then block, and execute the commands there.
Here again ${BASH_REMATCH[1]} is an array-access to an element of the array, which corresponds to the first matched group. ([0] would be the whole string.)
Another note: Both my scripts accept multi-line input and work on every line which matches. Non-matching lines are simply ignored. If you are inputting only one line, you don't need the loop, a simple if read ; then ... or even read && [[ $REPLY =~ $regex ]] && ... would be enough.
echo "$var" | pcregrep -o "(?<=yet more )text"
Well, for your simple example, you can do this:
var="text more text and yet more text"
echo $var | grep -e "yet more text" | grep -o "text"
I am attempting to write a one-line Perl script that will toggle a line in a configuration file from "commented" to not and back. I have the following so far:
perl -pi -e 's/^(#?)(\tDefaultServerLayout)/ ... /e' xorg.conf
I am trying to figure out what code to put in the replacement (...) section. I would like the replacement to insert a '#' if one was not matched on, and remove it if it was matched on.
pseudo code:
if ( $1 == '#' ) then
print $2
else
print "#$2"
My Perl is very rusty, and I don't know how to fit that into a s///e replacement.
My reason for this is to create a single script that will change (toggle) my display settings between two layouts. I would prefer to have this done in only one script.
I am open to suggestions for alternate methods, but I would like to keep this a one-liner that I can just include in a shell script that is doing other things I want to happen when I change layouts.
perl -pi -e 's/^(#?)(?=\tDefaultServerLayout)/ ! $1 && "#" /e' foo
Note the addition of ?= to simplify the replacement string by using a look-ahead assertion.
Some might prefer s/.../ $1 ? "" : "#" /e.