This is the error I get after compiling and running the file
./skript05.sh: 13: ./skript05.sh: Syntax error: word unexpected (expecting ")")
Here's the important snippet of the code, with line 13 pointed out. I don't think the rest of the code is needed since it works well, but if it is, let me know.
ls -l $1 | awk "
if($1 ~ /-([r-][w-][x-]){3}/)
{
MUCHLINES=$(system(\"egrep -o \"^[a-z ]{1,}$\" \", $9) | wc -l) ;#13
test -z "$MUCHLINES" && continue ;
print $9":"$MUCHLINES ;
>&2 echo "$9":"yes" ;
}
else >&2 echo "$9":"no" ;
"
What I can figure out is that it ignores symbols {} in lines 12 and 17, but I can't figure out why. All other parentheses are not ignored and highlighted properly when editing code in gedit for example.
I'm working on this in Linux.
I've been searching for answers on this for days, but can't seem to find any. If there are any, I'll apologize and delete this question. Thank you for any help!
(In case you need to know what is this code supposed to do — it should print into stdout "(nameoffile):(x)", where x is number of lines made up of only lowercase letters and spaces; and print into stderr "(nameoffile):yes/no" with yes in case of files (in ls -l known by having - as first symbol in access rights).)
#EdW - As others have pointed out, the script that you posted is a jumble, but I thought that the following might be helpful to you in that it does illustrate how one can combine ls, awk, and egrep in a bash script, more or less along the lines you seem to have had in mind. Please note, however, that it does NOT address some of the issues that others have raised, nor is it intended to serve as a model. It probably does not even do precisely what you want, but I hope you find it helpful in achieving some of your goals.
#!/bin/bash
ls -l $1 | awk '{print $1, $9}' | while read mask file
do
if [[ $mask =~ -([r-][w-][x-]){3} ]] ; then
MUCHLINES=$(egrep -o "^[a-z ]{1,}$" "$file" | wc -l)
if [[ $MUCHLINES -gt 0 ]] ; then
echo "$file:" $MUCHLINES
>&2 echo "$file:yes"
else
>&2 echo "$file:no"
fi
fi
done
Related
My objective here is to read each revision present in revisions.txt and extract the text against that revision number from logs.txt file.
For example revisions.txt file has the following inputs,
APP-1001
APP-1002
APP-1004
And logs.txt file has the following inputs,
APP-999 : Bug Fix for XYZ issues
APP-1001 : Bug Fix for XYZ issues
APP-1002 : Bug Fix for XYZ issues
APP-1003 : Bug Fix for XYZ issues
APP-1004 : Bug Fix for XYZ issues
I want to get all the lines against all revisions in the revisions.txt file. I came up with the following code,
#!/bin/bash
echo "Start!"
input=logs.txt
revision=revisions.txt
IFS=$'\n' read -d '' -r -a revs < $revision
for rev in "${revs[#]}"
do
echo $rev
while IFS='' read -r line || [[ -n "$line" ]]; do
regex='^'$rev'(.*)'
if [[ $line =~ $regex ]];
then
echo $line
fi
done < "$input"
done
Output as of now,
APP-1001
APP-1002
APP-1004
APP-1004 : Bug Fix for XYZ issues
It's only printing text for the last revision i.e. APP-1004. I read on the web that it's not possible to read two files in nested loop.
Please suggest a different way of doing this.
Thanks in advance.
You can nest the loops and hence, you can iterate from both files at the same time.
while read revisions_line
do
while read logs_line
do
echo "This line comes from revisions : $revisions_line"
echo "This line comes from logs : $logs_line"
done << "$( cat logs.txt)"
done << "$( cat revisions.txt)"
Regards!
You can simply use below script for the same:-
#!/bin/bash
while read line
do
#echo "$line logs.txt"
log_info=$(grep $line logs.txt)
if [ log_info != "" ]; then
echo "$log_info" | awk '{$1=$2=""; print $0}' | sed 's/^[ \t]*//'
fi
done < revisions.txt
How will it work? While loop will read each line from file revisions.txt and grep will search for that in logs.txt file and if found it will store that line in variable log_info. Now if log_info variable is not empty the line will be redirect to awk command and awk command will remove column1 and column2 from the line and redirect the output to sed command and finally sed will remove the leading blank space from it. The final out put will be:-
Bug Fix for XYZ issues
Bug Fix for XYZ issues
Bug Fix for XYZ issues
If you want the whole string just modify like below:-
echo "$log_info"
If you don't bother about the leading blank space you can go ahead with below:-
echo "$log_info" | awk '{$1=$2=""; print $0}'
I am new to shell script , i want to write a script to monitor CPU usage and if the CPU usage reaches a threshold it should print the CPU usage by top command ,here is my script , which is giving me error bad number and also not storing any value in the log files
while sleep 1;do if [ "$(top -n1 | grep -i ^cpu | awk '{print $2}')">>sy.log - ge "$Threshold" ]; then echo "$(top -n1)">>sys.log;fi;done
Your script HAS to be indented and stored to a file, especially if you are new to shell !
#!/bin/sh
while sleep 1
do
if [ "$(top -n1 | grep -i ^cpu | awk '{print $2}')">>sy.log - ge "$Threshold" ]
then
echo "$(top -n1)" >> sys.log
fi
done
Your condition looks a bit odd. It may work, but it looks really complex. Store intermediate results in variables, and evaluate them.
Then, you will immediately see the syntax error on the “-ge”.
You HAVE to store logfiles within an absolute path for security reasons. Use variables to simplify the reading.
#!/bin/sh
LOGFILE=/absolute_path/sy.log
WHOLEFILE=/absolute_path/sys.log
Thresold=80
while sleep 1
do
TOP="$(top -n1)"
CPU="$(echo $TOP | grep -i ^cpu | awk '{print $2}')"
echo $CPU >> $LOGFILE
if [ "$CPU" -ge "$Threshold" ] ; then
echo "$TOP" >> $WHOLEFILE
fi
done
You have a couple of errors.
If you write output to sy.log with a redirection then that output is no longer available to the shell. You can work around this with tee.
The dash before -ge must not be followed by a space.
Also, a few stylistic remarks:
grep x | awk '{y}' is a useless use of grep; this can usefully and more economically (as well as more elegantly) be rewritten as awk '/x/{y}'
echo "$(command)" is a useless use of echo -- not a deal-breaker, but you simply want command; there is no need to capture what it prints to standard output just so you can print that text to standard output.
If you are going to capture the output of top -n 1 anyway, there is no need really to run it twice.
Further notes:
If you know the capitalization of the field you want to extract, maybe you don't need to search case-insensitively. (I could not find a version of top which prints a CPU prefix with the load in the second field -- it the expression really correct?)
The shell only supports integer arithmetic. Is this a bug? Maybe you want to use Awk (which has floating-point support) to perform the comparison? This also allows for a moderately tricky refactoring. We make Awk output an exit code of 1 if the comparison fails, and use that as the condition for the if.
#!/bin/sh
while sleep 1
do
if top=$(top -n 1 |
awk -v thres="$Threshold" '1; # print every line
tolower($1) ~ /^cpu/ { print $2 >>"sy.log";
exitcode = ($2 >= thres ? 0 : 1) }
END { exit exitcode }')
then
echo "$top" >>sys.log
fi
done
Do you really mean to have two log files with nearly the same name, or is that a typo? Including a time stamp in the log might be useful both for troubleshooting and for actually using the log files.
I have a linux script that gets an argument passed to it that originates from MSDOS (actually DOSEMU running MS DOS 6.22). The argument that gets passed is case insensitive (as DOS didn't do cases) but of course Linux does.
I am trying to get from the following passed argument
/media/zigg4/vol1/database/scan/stalbans/docprint/wp23452.wpd
to
/media/zigg4/vol1/Database/SCAN/STALBANS/DOCPRINT/Wp23452.WPD
I do not know the actual case sensitive path so I need to somehow determine it from the argument that is passed to the script. I have absolutely no idea where to start with this so any help is greatly appreciated.
edited for extra information and clarity
UPDATE
Thanks to the answer by #anubhava I used the following:-
#!/bin/bash
copies=1
if [ ! -z "$2" ]; then
copies=$2
fi
find / -readable -ipath $1 2>&1 | grep -v "Permission denied" | while IFS= read -r FILE; do
lpr -o Collate=True -#$copies -sP $FILE
done
Works great :-)
You can use -ipath option of find for ignore case path matching:
# assuming $arg contains path argument supplied
find . -ipath "*$arg*"
I would employ awk for this (of course without salary)
#!/bin/bash
awk -varg="$1" -vactual="/media/zigg4/vol1/Database/SCAN/STALBANS/DOCPRINT/Wp23452.WPD" 'BEGIN{
if (tolower(arg)==tolower(actual)){
printf "Argument matches actual filepath\n"
}
}'
Run the script as
./script "/media/zigg4/vol1/database/scan/stalbans/docprint/wp23452.wpd"
Something like this:
if [ "$( echo $real | tr A-Z a-z )" = "$lower" ]; then
echo "matchy"
else
echo "no is matchy"
fi
Some notes:
tr is doing a to-lower translate.
The $( ... ) bit is placing the result of the enclosed command into a string.
You could do the translate on either side if you aren't sure if your "lower case" string can be trusted...
I am trying to parse each line of a file and look for a particular string. The script seems to be doing its intended job, however, in parallel it tries to execute the if command on line 6:
#!/bin/bash
for line in $(cat $1)
do
echo $line | grep -e "Oct/2015"
if($?==0); then
echo "current line is: $line"
fi
done
and I get the following (my script is readlines.sh)
./readlines.sh: line 6: 0==0: command not found
First: As Mr. Llama says, you need more spaces. Right now your script tries to look for a file named something like /usr/bin/0==0 to run. Instead:
[ "$?" -eq 0 ] # POSIX-compliant numeric comparison
[ "$?" = 0 ] # POSIX-compliant string comparison
(( $? == 0 )) # bash-extended numeric comparison
Second: Don't test $? at all in this case. In fact, you don't even have good cause to use grep; the following is both more efficient (because it uses only functionality built into bash and requires no invocation of external commands) and more readable:
if [[ $line = *"Oct/2015"* ]]; then
echo "Current line is: $line"
fi
If you really do need to use grep, write it like so:
if echo "$line" | grep -q "Oct/2015"; then
echo "Current line is: $line"
fi
That way if operates directly on the pipeline's exit status, rather than running a second command testing $? and operating on that command's exit status.
#Charles Duffy has a good answer which I have up-voted as correct (and it is), but here's a detailed, line by line breakdown of your script and the correct thing to do for each part of it.
for line in $(cat $1)
As I noted in my comment elsewhere this should be done as a while read construct instead of a for cat construct.
This construct will wordsplit each line making spaces in the file separate "lines" in the output.
All empty lines will be skipped.
In addition when you cat $1 the variable should be quoted. If it is not quoted spaces and other less-usual characters appearing in the file name will cause the cat to fail and the loop will not process the file.
The complete line would read:
while IFS= read -r line
An illustrative example of the tradeoffs can be found here. The linked test script follows. I tried to include an indication of why IFS= and -r are important.
#!/bin/bash
mkdir -p /tmp/testcase
pushd /tmp/testcase >/dev/null
printf '%s\n' '' two 'three three' '' ' five with leading spaces' 'c:\some\dos\path' '' > testfile
printf '\nwc -l testfile:\n'
wc -l testfile
printf '\n\nfor line in $(cat) ... \n\n'
let n=1
for line in $(cat testfile) ; do
echo line $n: "$line"
let n++
done
printf '\n\nfor line in "$(cat)" ... \n\n'
let n=1
for line in "$(cat testfile)" ; do
echo line $n: "$line"
let n++
done
let n=1
printf '\n\nwhile read ... \n\n'
while read line ; do
echo line $n: "$line"
let n++
done < testfile
printf '\n\nwhile IFS= read ... \n\n'
let n=1
while IFS= read line ; do
echo line $n: "$line"
let n++
done < testfile
printf '\n\nwhile IFS= read -r ... \n\n'
let n=1
while IFS= read -r line ; do
echo line $n: "$line"
let n++
done < testfile
rm -- testfile
popd >/dev/null
rmdir /tmp/testcase
Note that this is a bash-heavy example. Other shells do not tend to support -r for read, for example, nor is let portable. On to the next line of your script.
do
As a matter of style I prefer do on the same line as the for or while declaration, but there's no convention on this.
echo $line | grep -e "Oct/2015"
The variable $line should be quoted here. In general, meaning always unless you specifically know better, you should double-quote all expansion--and that means subshells as well as variables. This insulates you from most unexpected shell weirdness.
You decclared your shell as bash which means you will have there "Here string" operator <<< available to you. When available it can be used to avoid the pipe; each element of a pipeline executes in a subshell, which incurs extra overhead and can lead to unexpected behavior if you try to modify variables. This would be written as
grep -e "Oct/2015" <<<"$line"
Note that I have quoted the line expansion.
You have called grep with -e, which is not incorrect but is needless since your pattern does not begin with -. In addition you have full-quoted a string in shell but you don't attempt to expand a variable or use other shell interpolation inside of it. When you don't expect and don't want the contents of a quoted string to be treated as special by the shell you should single quote them. Furthermore, your use of grep is inefficient: because your pattern is a fixed string and not a regular expression you could have used fgrep or grep -F, which does string contains rather than regular expression matching (and is far faster because of this). So this could be
grep -F 'Oct/2015' <<<"$line"
Without altering the behavior.
if($?==0); then
This is the source of your original problem. In shell scripts commands are separated by whitespace; when you say if($?==0) the $? expands, probably to 0, and bash will try to execute a command called if(0==0) which is a legal command name. What you wanted to do was invoke the if command and give it some parameters, which requires more whitespace. I believe others have covered this sufficiently.
You should never need to test the value of $? in a shell script. The if command exists for branching behavior based on the return code of whatever command you pass to it, so you can inline your grep call and have if check its return code directly, thus:
if grep -F 'Oct/2015` <<<"$line" ; then
Note the generous whitespace around the ; delimiter. I do this because in shell whitespace is usually required and can only sometiems be omitted. Rather than try to remember when you can do which I recommend an extra one space padding around everything. It's never wrong and can make other mistakes easier to notice.
As others have noted this grep will print matched lines to stdout, which is probably not something you want. If you are using GNU grep, which is standard on Linux, you will have the -q switch available to you. This will suppress the output from grep
if grep -q -F 'Oct/2015' <<<"$line" ; then
If you are trying to be strictly standards compliant or are in any environment with a grep that doesn't know -q the standard way to achieve this effect is to redirect stdout to /dev/null/
if printf "$line" | grep -F 'Oct/2015' >/dev/null ; then
In this example I also removed the here string bashism just to show a portable version of this line.
echo "current line is: $line"
There is nothing wrong with this line of your script, except that although echo is standard implementations vary to such an extent that it's not possible to absolutely rely on its behavior. You can use printf anywhere you would use echo and you can be fairly confident of what it will print. Even printf has some caveats: Some uncommon escape sequences are not evenly supported. See mascheck for details.
printf 'current line is: %s\n' "$line"
Note the explicit newline at the end; printf doesn't add one automatically.
fi
No comment on this line.
done
In the case where you did as I recommended and replaced the for line with a while read construct this line would change to:
done < "$1"
This directs the contents of the file in the $1 variable to the stdin of the while loop, which in turn passes the data to read.
In the interests of clarity I recommend copying the value from $1 into another variable first. That way when you read this line the purpose is more clear.
I hope no one takes great offense at the stylistic choices made above, which I have attempted to note; there are many ways to do this (but not a great many correct) ways.
Be sure to always run interesting snippets through the excellent shellcheck and explain shell when you run into difficulties like this in the future.
And finally, here's everything put together:
#!/bin/bash
input_file="$1"
while IFS= read -r line ; do
if grep -q -F 'Oct/2015' <<<"$line" ; then
printf 'current line is %s\n' "$line"
fi
done < "$input_file"
If you like one-liners, you may use AND operator (&&), for example:
echo "$line" | grep -e "Oct/2015" && echo "current line is: $line"
or:
grep -qe "Oct/2015" <<<"$line" && echo "current line is: $line"
Spacing is important in shell scripting.
Also, double-parens is for numerical comparison, not single-parens.
if (( $? == 0 )); then
I am trying to find a clever way to figure out if the file passed to sed has been altered successfully or not.
Basically, I want to know if the file has been changed or not without having to look at the file modification date.
The reason why I need this is because I need to do some extra stuff if sed has successfully replaced a pattern.
I currently have:
grep -q $pattern $filename
if [ $? -eq 0 ]
then
sed -i s:$pattern:$new_pattern: $filename
# DO SOME OTHER STUFF HERE
else
# DO SOME OTHER STUFF HERE
fi
The above code is a bit expensive and I would love to be able to use some hacks here.
A bit late to the party but for the benefit of others, I found the 'w' flag to be exactly what I was looking for.
sed -i "s/$pattern/$new_pattern/w changelog.txt" "$filename"
if [ -s changelog.txt ]; then
# CHANGES MADE, DO SOME STUFF HERE
else
# NO CHANGES MADE, DO SOME OTHER STUFF HERE
fi
changelog.txt will contain each change (ie the changed text) on it's own line. If there were no changes, changelog.txt will be zero bytes.
A really helpful sed resource (and where I found this info) is http://www.grymoire.com/Unix/Sed.html.
I believe you may find these GNU sed extensions useful
t label
If a s/// has done a successful substitution since the last input line
was read and since the last t or T command, then branch to label; if
label is omitted, branch to end of script.
and
q [exit-code]
Immediately quit the sed script without processing any more input, except
that if auto-print is not disabled the current pattern space will be printed.
The exit code argument is a GNU extension.
It seems like exactly what are you looking for.
This might work for you (GNU sed):
sed -i.bak '/'"$old_pattern"'/{s//'"$new_pattern"'/;h};${x;/./{x;q1};x}' file || echo changed
Explanation:
/'"$old_pattern"'/{s//'"$new_pattern"'/;h} if the pattern space (PS) contains the old pattern, replace it by the new pattern and copy the PS to the hold space (HS).
${x;/./{x;q1};x} on encountering the last line, swap to the HS and test it for the presence of any string. If a string is found in the HS (i.e. a substitution has taken place) swap back to the original PS and exit using the exit code of 1, otherwise swap back to the original PS and exit with the exit code of 0 (the default).
You can diff the original file with the sed output to see if it changed:
sed -i.bak s:$pattern:$new_pattern: "$filename"
if ! diff "$filename" "$filename.bak" &> /dev/null; then
echo "changed"
else
echo "not changed"
fi
rm "$filename.bak"
You could use awk instead:
awk '$0 ~ p { gsub(p, r); t=1} 1 END{ exit (!t) }' p="$pattern" r="$repl"
I'm ignoring the -i feature: you can use the shell do do redirections as necessary.
Sigh. Many comments below asking for basic tutorial on the shell. You can use the above command as follows:
if awk '$0 ~ p { gsub(p, r); t=1} 1 END{ exit (!t) }' \
p="$pattern" r="$repl" "$filename" > "${filename}.new"; then
cat "${filename}.new" > "${filename}"
# DO SOME OTHER STUFF HERE
else
# DO SOME OTHER STUFF HERE
fi
It is not clear to me if "DO SOME OTHER STUFF HERE" is the same in each case. Any similar code in the two blocks should be refactored accordingly.
In macos I just do it as follows:
changes=""
changes+=$(sed -i '' "s/$to_replace/$replacement/g w /dev/stdout" "$f")
if [ "$changes" != "" ]; then
echo "CHANGED!"
fi
I checked, and this is faster than md5, cksum and sha comparisons
I know it is a old question and using awk instead of sed is perhaps the best idea, but if one wants to stick with sed, an idea is to use the -w flag. The file argument to the w flag only contains the lines with a match. So, we only need to check that it is not empty.
perl -sple '$replaced++ if s/$from/$to/g;
END{if($replaced != 0){ print "[Info]: $replaced replacement done in $ARGV(from/to)($from/$to)"}
else {print "[Warning]: 0 replacement done in $ARGV(from/to)($from/$to)"}}' -- -from="FROM_STRING" -to="$DESIRED_STRING" </file/name>
Example:
The command will produce the following output, stating the number of changes made/file.
perl -sple '$replaced++ if s/$from/$to/g;
END{if($replaced != 0){ print "[Info]: $replaced replacement done in $ARGV(from/to)($from/$to)"}
else {print "[Warning]: 0 replacement done in $ARGV(from/to)($from/$to)"}}' -- -from="timeout" -to="TIMEOUT" *
[Info]: 5 replacement done in main.yml(from/to)(timeout/TIMEOUT)
[Info]: 1 replacement done in task/main.yml(from/to)(timeout/TIMEOUT)
[Info]: 4 replacement done in defaults/main.yml(from/to)(timeout/TIMEOUT)
[Warning]: 0 replacement done in vars/main.yml(from/to)(timeout/TIMEOUT)
Note: I have removed -i from the above command , so it will not update the files for the people who are just trying out the command. If you want to enable in-place replacements in the file add -i after perl in above command.
check if sed has changed MANY files
recursive replace of all files in one directory
produce a list of all modified files
workaround with two stages: match + replace
g='hello.*world'
s='s/hello.*world/bye world/g;'
d='./' # directory of input files
o='modified-files.txt'
grep -r -l -Z -E "$g" "$d" | tee "$o" | xargs -0 sed -i "$s"
the file paths in $o are zero-delimited
$ echo hi > abc.txt
$ sed "s/hi/bye/g; t; q1;" -i abc.txt && (echo "Changed") || (echo "Failed")
Changed
$ sed "s/hi/bye/g; t; q1;" -i abc.txt && (echo "Changed") || (echo "Failed")
Failed
https://askubuntu.com/questions/1036912/how-do-i-get-the-exit-status-when-using-the-sed-command/1036918#1036918
Don't use sed to tell if it has changed a file; instead, use grep to tell if it is going to change a file, then use sed to actually change the file. Notice the single line of sed usage at the very end of the Bash function below:
# Usage: `gs_replace_str "regex_search_pattern" "replacement_string" "file_path"`
gs_replace_str() {
REGEX_SEARCH="$1"
REPLACEMENT_STR="$2"
FILENAME="$3"
num_lines_matched=$(grep -c -E "$REGEX_SEARCH" "$FILENAME")
# Count number of matches, NOT lines (`grep -c` counts lines),
# in case there are multiple matches per line; see:
# https://superuser.com/questions/339522/counting-total-number-of-matches-with-grep-instead-of-just-how-many-lines-match/339523#339523
num_matches=$(grep -o -E "$REGEX_SEARCH" "$FILENAME" | wc -l)
# If num_matches > 0
if [ "$num_matches" -gt 0 ]; then
echo -e "\n${num_matches} matches found on ${num_lines_matched} lines in file"\
"\"${FILENAME}\":"
# Now show these exact matches with their corresponding line 'n'umbers in the file
grep -n --color=always -E "$REGEX_SEARCH" "$FILENAME"
# Now actually DO the string replacing on the files 'i'n place using the `sed`
# 's'tream 'ed'itor!
sed -i "s|${REGEX_SEARCH}|${REPLACEMENT_STR}|g" "$FILENAME"
fi
}
Place that in your ~/.bashrc file, for instance. Close and reopen your terminal and then use it.
Usage:
gs_replace_str "regex_search_pattern" "replacement_string" "file_path"
Example: replace do with bo so that "doing" becomes "boing" (I know, we should be fixing spelling errors not creating them :) ):
$ gs_replace_str "do" "bo" test_folder/test2.txt
9 matches found on 6 lines in file "test_folder/test2.txt":
1:hey how are you doing today
2:hey how are you doing today
3:hey how are you doing today
4:hey how are you doing today hey how are you doing today hey how are you doing today hey how are you doing today
5:hey how are you doing today
6:hey how are you doing today?
$SHLVL:3
Screenshot of the output:
References:
https://superuser.com/questions/339522/counting-total-number-of-matches-with-grep-instead-of-just-how-many-lines-match/339523#339523
https://unix.stackexchange.com/questions/112023/how-can-i-replace-a-string-in-a-files/580328#580328