How To Create Simple Log File From Script - linux

I'm trying to create a simple log file called "users.txt" that contains the username, full name, and home directory of the username entered. I also want to include the time that the script was initially running.
Any suggestions?
The script name is called catbash.sh
I have tried things such as
catbash.sh > user.txt
But I have no idea how to get specific information etc.
clear
LOGFILE=/home/student/gg193/FileTypes/TextFiles/ShellScripts/user.txt
read -p "What is your username?" username
read -p "May I know your name please? " name surname
echo "$(date) $username $name $surname $LOGFILE" >> $LOGFILE
TIME=$(date "+%H")
if [ $TIME -ge 0 -a $TIME -lt 12 ]
then
echo "\nGood Morning, $surname"
elif [ $TIME -ge 12 -a $TIME -lt 18 ]
then
echo "\nGood afternoon $surname"
else
echo "\nGood evening $surname"
fi
echo "1. nonblank\n2. number\n3. ends\n4. nends\n"
while :
do
read INPUT_STRING
case $INPUT_STRING in
nonblank)
NonEmptyLine=$(cat catbash.sh | sed '/^\s*$/d' | wc -l)
echo "\nNumber of Non-Empty Lines are:" $NonEmptyLine
break
;;
number)
EmptyLine=$(grep -cvP '\S' catbash.sh)
echo "\nNumber of Empty Lines are:" $EmptyLine
break
;;
ends)
echo "================================================================================="
sed 's/$/$/' catbash.sh
echo "================================================================================="
break
;;
nends)
NonEmptyLine=$(cat catbash.sh | sed '/^\s*$/d' | wc -l)
echo "\nNumber of Non-Empty Lines are:" $NonEmptyLine
EmptyLine=$(grep -cvP '\S' catbash.sh)
echo "\nNumber of Empty Lines are:" $EmptyLine
echo "================================================================================="
sed 's/$/$/' catbash.sh
echo "================================================================================="
break
;;
*)
echo "\nSorry, I don't understand"
;;
esac
done
DURATION=$(ps -o etime= -p "$$")
echo "\nAmount of time that has passed since the script was initially executed:" $DURATION
echo "\nThanks for using catbash.sh!"

You have to do the logging from inside the sh script. For ex, you could echo the info that you want on the terminal (which you are already doing) and then append | tee -a $LOGFILE (define LOGFILE at the top so you only have to change once if you need a different file name/location).
As further improvements you can look at defining your own logger function or even explore existing ones. For ex a simpler logger func could take 2 args - message, file name. The message itself could be composed of the user name, date/timestamp etc as you want.
With the info currently in your question, this is the best pointer I can give.

Related

Using sed after cat << 'EOT' to substitute just one variable inside the generated script

I'm building a script for php-fpm compilation, installation and deployment in ubuntu 14. At one point, I have got to generate another file using this main script. The resulting file is a script and should have all variables BUT one NOT expanded.
So I started with cat << 'EOT' in will of resolving the thing after the file generation with sed. But I find myself in a "logic" blackhole.
As for the EOT quoting beeing an issue for expanding just one variable, the same is for the sed line. I went straight writing the following, then laught at it without even executing it, of course.
sed -i 's/\$PhpBuildVer\/$PhpBuildVer' /etc/init.d/php-$PhpBuildVer-fpm
OR
sed -i "s/\$PhpBuildVer\/$PhpBuildVer" /etc/init.d/php-$PhpBuildVer-fpm
both would fail, while I need the first pattern to be the "$PhpBuildVer" itself and the other one beeing the expanded variable, for instance, 7.1.10.
How would I perform this substituion with either sed or another GNU Linux command?
This is my script, most of the parts have been cut-off as non question related.
#!/bin/bash
PhpBuildVer="7.1.10"
... #removed non relevant parts of the script
cat << 'EOT' >> /etc/init.d/php-$PhpBuildVer-fpm
#! /bin/sh
### BEGIN INIT INFO
# Provides: php-$PhpBuildVer-fpm
# Required-Start: $all
# Required-Stop: $all
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: starts php-$PhpBuildVer-fpm
# Description: starts the PHP FastCGI Process Manager daemon
### END INIT INFO
php_fpm_BIN=/opt/php-$PhpBuildVer/sbin/php-fpm
php_fpm_CONF=/opt/php-$PhpBuildVer/etc/php-fpm.conf
php_fpm_PID=/opt/php-$PhpBuildVer/var/run/php-fpm.pid
php_opts="--fpm-config $php_fpm_CONF"
wait_for_pid () {
try=0
while test $try -lt 35 ; do
case "$1" in
'created')
if [ -f "$2" ] ; then
try=''
break
fi
;;
'removed')
if [ ! -f "$2" ] ; then
try=''
break
fi
;;
esac
echo -n .
try=`expr $try + 1`
sleep 1
done
}
case "$1" in
start)
echo -n "Starting php-fpm "
$php_fpm_BIN $php_opts
if [ "$?" != 0 ] ; then
echo " failed"
exit 1
fi
wait_for_pid created $php_fpm_PID
if [ -n "$try" ] ; then
echo " failed"
exit 1
else
echo " done"
fi
;;
stop)
echo -n "Gracefully shutting down php-fpm "
if [ ! -r $php_fpm_PID ] ; then
echo "warning, no pid file found - php-fpm is not running ?"
exit 1
fi
kill -QUIT `cat $php_fpm_PID`
wait_for_pid removed $php_fpm_PID
if [ -n "$try" ] ; then
echo " failed. Use force-exit"
exit 1
else
echo " done"
echo " done"
fi
;;
force-quit)
echo -n "Terminating php-fpm "
if [ ! -r $php_fpm_PID ] ; then
echo "warning, no pid file found - php-fpm is not running ?"
exit 1
fi
kill -TERM `cat $php_fpm_PID`
wait_for_pid removed $php_fpm_PID
if [ -n "$try" ] ; then
echo " failed"
exit 1
else
echo " done"
fi
;;
restart)
$0 stop
$0 start
;;
reload)
echo -n "Reload service php-fpm "
if [ ! -r $php_fpm_PID ] ; then
echo "warning, no pid file found - php-fpm is not running ?"
exit 1
fi
kill -USR2 `cat $php_fpm_PID`
echo " done"
;;
*)
echo "Usage: $0 {start|stop|force-quit|restart|reload}"
exit 1
;;
esac
EOF
#Here the variable should be substituted.
chmod 755 /etc/init.d/php-$PhpBuildVer-fpm
... #removed non relevant parts of the script
I am not 100% sure, but I think what you are looking for is:
sed -i 's/\$PhpBuildVer/'"$PhpBuildVer"'/' /etc/init.d/php-$PhpBuildVer-fpm
You can actually put two quoted expressions right next to each other in bash. E.g., echo '12'"34"'56' will output 123456. In this case, the first \$PhpBuildVer is in '' so it can match literally, and the second is in "" so that it will be expanded.
(But maybe you should consider using a template file and php, or (blatant plug)
perlpp* to build the script, rather than inlining all the text into your main script. ;) )
Edit by the way, using cat ... >> rather than cat ... > means you will be appending to the script unless you have rmed it somewhere in the code you didn't show.
Edit 2 If $PhpBuildVer has any characters in it that sed interprets in the replacement text, you might need to escape it:
repl_text="$(sed -e 's/[\/&]/\\&/g' <<<"$PhpBuildVer")"
sed -i 's/\$PhpBuildVer/'"$repl_text"'/' /etc/init.d/php-$PhpBuildVer-fpm
Thanks to this answer by Pianosaurus.
Tested example
I put this in make.sh:
#!/bin/bash
f=42 # The variable we are going to substitute
cat <<'EOT' >"test-$f.sh" # The script we are generating
#!/bin/sh
# Provides: test-$f.sh
echo 'Hello, world!'
EOT
echo "test-$f.sh before substitution is:"
echo "---------"
cat "test-$f.sh"
echo "---------"
sed -i 's/\$f/'"$f"'/' "test-$f.sh" # The substitution, from above
echo "test-$f.sh after substitution is:"
echo "---------"
cat "test-$f.sh"
echo "---------"
The output I get is:
test-42.sh before substitution is:
---------
#!/bin/sh
# Provides: test-$f.sh
echo 'Hello, world!'
---------
(note the literal $f)
test-42.sh after substitution is:
---------
#!/bin/sh
# Provides: test-42.sh
echo 'Hello, world!'
---------
(now the $f is gone, and has been replaced with its value, 42)
perlpp example
Since *I am presently the maintainer of perlpp, I'll give you that example, too :) . In a template file that I called test.template, I put:
#!/bin/sh
# Provides: test-<?= $S{ver} ?>.sh
echo 'Hello, world!'
That was exactly the content of the script I wanted, but with <?= $S{ver} ?> where I wanted to do the substitution. I then ran
perlpp -s ver=\'7.1.10\' test.template
(with escaped quotes to pass them to perl) and got the output:
#!/bin/sh
# Provides: test-7.1.10.sh
echo 'Hello, world!'
:)
Any -s name=\'value\' command-line argument to perlpp creates $S{name}, which you can refer to in the template.
<?= expr ?> prints the value of expression expr
Therefore, <?= $S{name} ?> outputs the value given on the command line for name.
Just break up the heredoc. eg
cat > file << 'EOF'
This line will not be interpolated: $FOO
EOF
cat >> file << EOF
and this line will: $FOO
EOF
If for some reason you do want to used sed as well, don't do it after, just use it instead of cat:
sed 's#foo#bar#g' >> file << EOF
this line's foo is changed by sed, with interpolated $variables
EOF

Bash:Else not working in if/else statement in case statement

I am trying to check if a user types multiple arguments in a command line using case and if/else statements. What's wrong is that I keep getting the default case instead of the same command, but with 2 more arguments. For instance, one of my conditions is:
del)
if [ -z "$2" ] || [ -z "$3" ]
then
echo "Usage: removes a file"
else
echo "using Bash command: rm $2 $3"
rm $2 $3
echo done
fi
prints the first condition, but if I type, say, del aaa bbb, I get the default case, which is:
echo "ERROR: Unrecognized command"
I'm also using this to read a user's input, if that helps.
read -p "wcl> " -r wcl $2 $3
I don't really know if there's a better way to solve this without scrapping all my code and starting from scratch.
This is the full code:
#!/bin/bash
#use read command
echo Welcome to the Windows Command Line simulator!
echo Enter your commands below
while true
do
read -p "wcl> " -r wcl $2 $3
case $wcl in
dir)
echo "using Bash command: ls $2 $3"
ls
continue
;;
copy)
FILE="$2"
if [ "$#" -ne 3 ]
then
echo "Usage: copy sourcefile destinationfile"
else
echo "using Bash command: cp $2 $3"
if [ -f "$FILE" ]
then
cp $2 $3
else
echo "cannot stat $FILE: No such file or directory">&2
fi
echo done
fi
continue
;;
del)
if [ -z "$2" ] || [ -z "$3" ]
then
echo "Usage: removes a file"
else
echo "using Bash command: rm $2 $3"
rm $2 $3
echo done
fi
continue
;;
move)
if [ -z "$2" ] || [ -z "$3" ]
then
echo "Usage: moves a file to another file name and location"
else
echo "using Bash command: mv $2 $3"
mv $2 $3
echo done
fi
continue
;;
rename)
if [ -z "$2" ] || [ -z "$3" ]
then
echo "Usage: renames a file"
else
echo "using Bash command: mv $2 $3"
mv $2 $3
echo done
fi
continue
;;
ipconfig)
ifconfig eth0 | grep "inet addr" | cut -d ':' -f 2 | cut -d ' ' -f 1
continue
;;
exit)
echo "Goodbye"
exit 1
;;
^c)
echo "Goodbye"
exit 1
;;
*)
echo "ERROR: Unrecognized command"
continue
esac
done
You can't use read to set the positional parameters, although it isn't clear why you would need to here. Just use regular parameters.
while true
do
read -p "wcl> " -r wcl arg1 arg2
case $wcl in
dir)
echo "using Bash command: ls $arg1 $arg2"
ls "$arg1" "$arg2"
continue
;;
# ...
esac
done
The way read -r wcl $2 $3 is executed is that $2 and $3 are first expanded to give names that read will use to set variables. If those aren't set, then the command reduces to read -r wcl, and so your entire command line is assigned to the variable wcl, not just the command.
However, read by itself is not going to do the same parsing that the shell already does, if you goal is to write your own shell.
If you are really using bash, you can insert the words you read into positional parameters through an array. (You could also just leave them in the array, but the syntax for referring to positional parameters is simpler.)
# -a: read the successive words into an array
read -r -p "wcl> " -a params
# set the positional parameters to the expansion of the array
set -- "${params[#]}"
wcl=$1 # Or you could do the case on "$1"
This will also set $# to the number of words read, as a side-effect of setting the positional parameters.
As #chepner points outs, the read is problematic: It simply splits the input into whitespace-separated words, without respecting quotes, backslashes, and whatever other shell metacharacters you might want to implement. Doing a full bash-style parse of a command-line in bash itself would be quite a difficult exercise.

Bash: Counting instances of a string in text file with a loop

I am trying to write a simple bash script in which it takes in a text file, loops through the file and tells me how many times a certain string appears in the file. I want to eventually use this for a custom log searcher (for instance, search for the words 'log in' in a particular log file, etc.), but am having some difficulty as I am relatively new to bash. I want to be able to quickly search different logs for different terms at my will and see how many times they occur. Everything works perfectly until I get down to my loops. I think that I am using grep wrong, but am unsure if that is the issue. My loop codes may seem a little strange because I have been at it for a while and have been constantly tweaking things. I have done a bunch of searching but I feel like I am the only one who has ever had this issue (hopefully not because it is incredibly simple and I just suck). Any and all help is greatly appreciated, thanks in advance everyone.
edit: I would like to account for every instance of the string and not just
one instance per line
#!/bin/bash
echo "This bash script counts the instances of a user-defined string in a file."
echo "Enter a file to search:"
read fileName
echo " "
echo $path
if [ -f "$fileName" ] || [ -d "$fileName" ]; then
echo "File Checker Complete: '$fileName' is a file."
echo " "
echo "Enter a string that you would like to count the occurances of in '$fileName'."
read stringChoice
echo " "
echo "You are looking for '$stringChoice'. Counting...."
#TRYING WITH A WHILE LOOP
count=0
cat $fileName | while read line
do
if echo $line | grep $stringChoice; then
count=$[ count + 1 ]
done
echo "Finished processing file"
#TRYING WITH A FOR LOOP
# count=0
# for i in $(cat $fileName); do
# echo $i
# if grep "$stringChoice"; then
# count=$[ $count + 1 ]
# echo $count
# fi
# done
if [ $count == 1 ] ; then
echo " "
echo "The string '$stringChoice' occurs $count time in '$fileName'."
elif [ $count > 1 ]; then
echo " "
echo "The string '$stringChoice' occurs $count times in '$fileName'."
fi
elif [ ! -f "$fileName" ]; then
echo "File does not exist, please enter the correct file name."
fi
To find and count all occurrences of a string, you could use grep -o which matches only the word instead of the entire line and pipe the result to wc
read string; grep -o "$string" yourfile.txt | wc -l
You made basic syntax error in the code. Also, the variable of count was never updating as the the while loop was being executed in a subshell and thus the updated count value was never reflecting back.
Please change your code to the following one to get desired result.
#!/bin/bash
echo "This bash script counts the instances of a user-defined string in a file."
echo "Enter a file to search:"
read fileName
echo " "
echo $path
if [ -f "$fileName" ] ; then
echo "File Checker Complete: '$fileName' is a file."
echo " "
echo "Enter a string that you would like to count the occurances of in '$fileName'."
read stringChoice
echo " "
echo "You are looking for '$stringChoice'. Counting...."
#TRYING WITH A WHILE LOOP
count=0
while read line
do
if echo $line | grep $stringChoice; then
count=`expr $count + 1`
fi
done < "$fileName"
echo "Finished processing file"
echo "The string '$stringChoice' occurs $count time in '$fileName'."
elif [ ! -f "$fileName" ]; then
echo "File does not exist, please enter the correct file name."
fi

greping a character from file UNIX.linux bash. Can't pass an argument(file name) through command line

I am having trouble with my newbie linux script which needs to count brackets and tell if they are matched.
#!/bin/bash
file="$1"
x="()(((a)(()))"
left=$(grep -o "(" <<<"$x" | wc -l)
rght=$(grep -o ")" <<<"$x" | wc -l)
echo "left = $left right = $rght"
if [ $left -gt $rght ]
then echo "not enough brackets"
elif [ $left -eq $rght ]
then echo "all brackets are fine"
else echo "too many"
fi
the problem here is i can't pass an argument through command line so that grep would work and count the brackets from the file. In the $x place I tried writing $file but it does not work
I am executing the script by writting: ./script.h test1.txt the file test1.txt is on the same folder as script.h
Any help in explaining how the parameter passing works would be great. Or maybe other way to do this script?
The construct <<< is used to transmit "the contents of a variable", It is not applicable to "contents of files". If you execute this snippet, you could see what I mean:
#!/bin/bash
file="()(((a)((a simple test)))"
echo "$( cat <<<"$file" )"
which is also equivalent to just echo "$file". That is, what is being sent to the console are the contents of the variable "file".
To get the "contents of a file" which name is inside a var called "file", then do:
#!/bin/bash
file="test1.txt"
echo "$( cat <"$file" )"
which is exactly equivalent to echo "$( <"$file" )", cat <"$file" or even <"$file" cat
You can use: grep -o "(" <"$file" or <"$file" grep -o "("
But grep could accept a file as a parameter, so this: grep -o "(" "$file" also works.
However, I believe that tr would be a better command, as this: <"$file" tr -cd "(".
It transforms the whole file into a sequence of "(" only, which will need a lot less to be transmitted (passed) to the wc command. Your script would become, then:
#!/bin/bash -
file="$1"
[[ $file ]] || exit 1 # make sure the var "file" is not empty.
[[ -r $file ]] || exit 2 # test if the file "file" exists.
left=$(<"$file" tr -cd "("| wc -c)
rght=$(<"$file" tr -cd ")"| wc -c)
echo "left = $left right = $rght"
# as $left and $rght are strictly numeric values, this integer tests work:
(( $left > $rght )) && echo "not enough right brackets"
(( $left == $rght )) && echo "all brackets are fine"
(( $left < $rght )) && echo "too many right brackets"
# added as per an additional request of the OP.
if [[ $(<"$file" tr -cd "()"|head -c1) = ")" ]]; then
echo "the first character is (incorrectly) a right bracket"
fi

BASH If [[ "$a" == *"$b"* ]] Always true even when it shouldn't be

I am trying to write a small bash script to monitor the output of RiotShield (a 3rd party player scraper for League of Legends) for crashes. If a keyword is found in the log it should kill the process and restart it.
Here is my bash script as is:
#!/bin/bash
crash[1]="disconnected"
crash[2]="38290209"
while true; do
list=$(tail log.log)
#clear
echo "Reading Log"
echo "========================================"
echo $list
for item in ${list//\\n/ }
do
for index in 1 2
do
c=${crash[index]}
#echo "Crash Word:" $c
if [[ "$c" == *"$item"* ]]; then
echo "RiotShield has crashed."
echo "Killing RiotShield."
kill $(ps aux | grep '[R]iotShield.exe' | awk '{print $2}')
echo "RiotShield killed!"
echo "Clearing log."
echo > log.log
echo "Starting RiotShield"
(mono RiotShield.exe >> log.log &)
fi
done
done
sleep 10
done
My crash array are keywords that I know show in the log when it crashes. I have 38290209 in there only for testing purposes as it is my summoner ID on League of Legends and the moment I preform a search for my Summoner name the ID shows in the log.
The problem is even when disconnected and 38290209 do not show up in the log my
if [[ "$c" == *"$item"* ]]; then
fires, kills the RiotShield process and then relaunches it.
The length of the crash array will grow as I find more keywords for crashes so I cant just do
if [[ "$c" == "*disconnected*" ]]; then
Please and thanks SOF
EDIT:
Adding working code:
#!/bin/bash
crash[1]="disconnected"
crash[2]="error"
while true; do
list=$(tail log.log)
clear
echo "Reading Log"
echo "========================================"
echo $list
for index in 1 2
do
c=${crash[index]}
#echo "Crash Word:" $c
if [[ $list == *$c* ]]; then
echo "RiotShield has crashed."
echo "Crash Flag: " $c
echo "Killing RiotShield."
kill $(ps aux | grep '[R]iotShield.exe' | awk '{print $2}')
echo "RiotShield killed!"
echo "Clearing log."
echo > log.log
echo "Starting RiotShield"
(mono RiotShield.exe >> log.log &)
fi
done
sleep 10
done
I think you have the operands in your expression the wrong way around. It should be:
if [[ $item == *$c* ]]; then
because you want to see if a keyword ($c) is present in the line ($item).
Also, I'm not sure why you need to break the line into items by doing this: ${list//\\n/ }. You can just match the whole line.
Also note that double-quotes are not required within [[.

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