Read from a log file - bash

I want compile a bash script with selection of what i want to search
./mybash log.txt
root#usa18:/home#muster?: ERROR
list of all lines containing ERROR
end or search again?: exit
#!/bin/bash
input=$1
while cat $1; read -p "muster?:" | sed -n -e '/$muster/p' >output.txt;
if...(thats not my biggest problem)
fi
done < $1

Is this something similar to what you hope to do?
#!/bin/bash
read -p "search string:" muster
saved="$IFS"
IFS=$'\n'
for i in $(grep -i $muster $1); do
# $i now contains the line of which did match the search string
done
IFS="$saved"

Here is another version:
#!/bin/bash
# Check the numer of parameters
if (( $# > 0 ))
then
input="$1" # Always enclose filename with quotes
else
echo "USAGE: $0 filename" >&2
exit 1
fi
while : # true
do
read -p "muster?:" muster
grep "$muster" "$input"
read -p "Search again?:" ans
if [[ $ans == [nN]* ]]
then
break
fi
done

Sorry for the bad explain
i resolved thank your help
my problem was i did understand die difference from " and '
#!/bin/bash
input=$1
read -p "what want you search? :" SEARCH
grep -e "{SEARCH}" "$1" > newlog.txt

Related

Create an script that reads variables from the console and replace this values for the ones wrapped in curly brackets

I have a small assignment and this is the part that I am stuck on.
I have been given a text, and within the text there are strings like : {adjective},{noun} and so on. My script should allow the user to write whatever he/she wants in the console and I will replace those words in the text.
My approach so far is to make a for loop iterating through each line and somehow to use sed but I don't know how.
Any hint or help is highly appreciated.
Thank you in prior.
EDIT:
With my code so far I am able to replace the adjectives and I can't think of a way to use if statements to do the others.
Sorry for the lack of knowledge towards this site.
i=1
while [ $i -le 20 ]
do
echo Please enter an adjective :
read var
sed -i "s/{adjective}/$var/g" file.txt
i=$((i + 1))
done
cat file.txt
Here's an example file.txt file:
The {adjective} fox jumped over the lazy {animal}.
And here's a sample run:
Please enter a(n) adjective: quick
Please enter a(n) animal: dog
And here's the expected result.
$ cat file.txt
The quick fox jumped over the lazy dog.
Best scripts are always non interactive. I have written your task as below :
Script
#!/bin/bash
[[ $# -gt 6 ]] && echo "Too many arguments!! "
while [[ $# -ne 0 ]]
do
[[ $1 == "--adj" ]] && { shift; adj=$1; shift; continue ; }
[[ $1 == "--noun" ]] && { shift; noun=$1; shift; continue ; }
[[ $1 == "--file" ]] && { shift; file=$1; shift; continue ; }
echo "Unkwown option $1" && exit 1
done
[[ -z "$file" ]] && { echo "You must specify a --file parameter" ; exit 2 ; }
[[ ! -z "$adj" ]] && sed -i "s/{adjective}/$adj/g" "$file"
[[ ! -z "$noun" ]] && sed -i "s/{noun}/$noun/g" "$file"
input.txt
You are a {adjective} {noun}
Usage
./populate.sh --noun 'mama' --adj 'big' --file input.txt
Resulting file
$ cat input.txt
You are a big mama
Hope this helps you.
Here's a solution that may work for you:
file=$1
for variable in $( grep -o '{[^}]*}' $file )
do
read -p "Please enter a(n) $variable: " var
sed -i.bk -e "s/$variable/$var/" $file
done
Here's a sample invocation:
$ cat file.txt
The {adjective} fox jumped over the lazy {animal}.
$ ./madlibs.sh file.txt
Please enter a(n) {adjective}: quick
Please enter a(n) {animal}: dog
$ cat file.txt
The quick fox jumped over the lazy dog.

how can I loop with an error message?

Latest Version
#!/bin/bash
set -e
shopt -s nocasematch
#vars
redbgbold='\e[1;97;41m'
resetcolor='\e[0m'
RegExFQDN='(?=^.{4,253}$)(^((?!-)[a-zA-Z0-9-]{1,63}(?<!-)\.)+[a-zA-Z]{2,63}$)'
#functions
ask() {
local input
until
read -rp "$1 > " input >&2 || return 1
grep -q -P "$2" <<< "$input"
do
printf "ERROR - "${redbgbold}"\"$input\""${resetcolor}" is not a valid " >&2; sed "s/.*the //" <<< "$1" >&2
done
printf '%s\n' "$input"
}
#code
while [ -z $fqdn ]; do
fqdn=$(ask "Enter the FQDN" $RegExFQDN)
echo "FQDN is $fqdn"
done
The Question
I have a read line, and I want to take what the user entered and see if it matches my regex, if it matches we leave the loop, if it fails it prints an error and we do the loop again until we get a match. It looks redundant to me, and I assume there should be a better way but not sure what that should be.
Original Code
#!/bin/bash
set -e
shopt -s nocasematch
function RegexValidation() {
if [ "$2" = "fqdn" ]; then
if [ `echo $1 | grep -c -P '(?=^.{1,254}$)(^(?>(?!\d+\.)[a-z0-9_\-]{1,63}\.?)+(?:[a-z]{2,})$)'` == "0" ]; then
echo "ERROR - $1 is not a valid FQDN"
unset $!{1}
fi
fi
}
while [ -z $fqdn ]; do
read -e -r -p "Enter the Fully Qualified Domain Name > " fqdn
RegexValidation $fqdn fqdn
done
shopt -u nocasematch
any help is appreciated.
Update #1 - fixed formatting issues.
Update #2 - using that other guy's suggestions with a few additional tweaks
I would do basically the same thing, but split it differently to make it easier to reuse:
#!/bin/bash
set -e
ask() {
local input
until
read -rp "$1 > " input >&2 || return 1
grep -q -P "$2" <<< "$input"
do
echo "Invalid answer. Try again" >&2
done
printf '%s\n' "$input"
}
ask_fqdn() {
ask "$1" '(?=^.{1,254}$)(^(?>(?!\d+\.)[a-z0-9_\-]{1,63}\.?)+(?:[a-z]{2,})$)'
}
fqdn=$(ask_fqdn "Enter first FQDN")
echo "You wrote $fqdn"
fqdn=$(ask_fqdn "Enter second FQDN")
echo "This time it was $fqdn"
number=$(ask "And now a number because why not" '^\d+$')
echo "So $number"
Now you don't have to write a new loop every time you want new information, and you can easily ask for new things without modifying the existing functions.
Have the function return a status, which you can test with if in the loop.
And rather than use test to check the result of grep, just test it directly with if. grep returns a non-zero status if the input doesn't match.
function RegexValidation() {
if [ "$2" = "fqdn" ]; then
if ! echo "$1" | grep -q -P '(?=^.{1,254}$)(^(?>(?!\d+\.)[a-z0-9_\-]{1,63}\.?)+(?:[a-z]{2,})$)'; then
echo "ERROR - $1 is not a valid FQDN"
return 1
fi
return 0
fi
}
while :; do
read -e -r -p "Enter the Fully Qualified Domain Name > " fqdn
if RegexValidation "$fqdn" fqdn
then break
fi
done
Also, remember to quote your variables.

Bash associative arrays error

I seem to have this problem. This code breaks at line 119 in my script with bash associative arrays. I am sorry for the comments but I am kind to new to bash scripting. This is the code:
#!/bin/bash
# Aliases file
# Command usage: cpRecent/mvRecent -d {dirFrom},{dirTo} -n {numberofFiles} -e {editTheNames}
# Error codes
NO_ARGS="You need to pass in an argument"
INVALID_OPTION="Invaild option:"
NO_DIRECTORY="No directory found"
# Return values
fullpath=
directories=
numfiles=
interactive=
typeset -a files
typeset -A filelist
# Advise that you use relative paths
__returnFullPath(){
local npath
if [[ -d $1 ]]; then
cd "$(dirname $1)"
npath="$PWD/$(basename $1)"
npath="$npath/" #Add a slash
npath="${npath%.*}" #Delete .
fi
fullpath=${npath:=""}
}
__usage(){
wall <<End-Of-Message
________________________________________________
<cpRecent/mvRecent> -d "<d1>,<d2>" -n <num> [-i]
-d First flag: Takes two arguments
-n Second flag: Takes one argument
-i Takes no arguments. Interactive mode
d1 Directory we are reading from
d2 Directory we are writing to
num Number of files
________________________________________________
End-Of-Message
}
__processOptions(){
while getopts ":d:n:i" opt; do
case $opt in
d ) IFS=',' read -r -a directories <<< "$OPTARG";;
n ) numfiles=$OPTARG;;
i ) interactive=1;;
\? ) echo "$INVALID_OPTION -$OPTARG" >&2 ; return 1;;
: ) echo "$NO_ARGS"; __usage; return 1;;
* ) __usage; return 1;;
esac
done
}
__getRecentFiles(){
# Check some conditions
(( ${#directories[#]} != 2 )) && echo "$INVALID_OPTION Number of directories must be 2" && return 2
#echo ${directories[0]} ${directories[1]}
# Get the full paths of the directories to be read from/written to
__returnFullPath "${directories[0]}"
directories[0]="$fullpath"
__returnFullPath "${directories[1]}"
directories[1]="$fullpath"
if [[ -z ${directories[0]} || -z ${directories[1]} ]]; then
echo $NO_DIRECTORY
return 3
fi
[[ numfiles != *[!0-9]* ]] && echo "$INVALID_OPTION Number of files cannot be a string" && return 4
#numfiles=$(($numfiles + 0))
(( $numfiles == 0 )) && echo "$INVALID_OPTION Number of files cannot be zero" && return 4
local num="-"$numfiles""
# Get the requested files in directory(skips directories)
if [[ -n "$(ls -t ${directories[0]} | head $num)" ]]; then
# For some reason using local -a or declare -a does not seem to split the string into two
local tempfiles=($(ls -t ${directories[0]} | head $num))
#IFS=' ' read -r -a tempfiles <<< "$string"
#echo ${tempfiles[#]}
for index in "${!tempfiles[#]}"; do
echo $index ${tempfiles[index]}
[[ -f "${directories[0]}${tempfiles[index]}" ]] && files+=("${tempfiles[index]}")
done
fi
}
####################################
# The problem is this piece of code
__processLines(){
local name
local answer
local dirFrom
local dirTo
if [[ -n $interactive ]]; then
for (( i=0; i< ${#files[#]}; i++ )); do
name=${files[i]}
read -n 1 -p "Old name: $name. Do you wish to change the name(y/n)?" answer
[[ answer="y" ]] && read -p "Enter new name:" name
dirFrom="${directories[0]}${files[i]}"
dirTo="${directories[1]}$name"
fileslist["$dirFrom"]="$dirTo"
done
else
for line in $files; do
dirFrom="${directories[0]}$line"
echo $dirFrom # => /home/reclusiarch/Documents/test
dirTo="${directories[1]}$line"
echo $dirTo # => /home/reclusiarch/test
fileslist["$dirFrom"]="$dirTo" # This is the offending line
done
fi
}
###########################################################
cpRecent(){
__processOptions $*
__getRecentFiles
__processLines
for line in "${!filelist[#]}"; do
cp $line ${filelist[$line]}
done
echo "You have copied ${#fileList[#]} files"
unset files
unset filelist
return
}
mvRecent(){
__processOptions $*
__getRecentFiles
__processLines
for line in "${!filelist[#]}"; do
mv $line ${filelist[$line]}
done
echo "You have copied ${#fileList[#]} files"
unset files
unset filelist
return
}
cpRecent "$*"
I have tried a lot of things. To run the script,
$ bash -x ./testing.sh -d "Documents,." -n 2
But nothing seems to work:
The error is this(when using bash -x):
./testing.sh: line 119: /home/reclusiarch/Documents/test: syntax error: operand expected (error token is "/home/reclusiarch/Documents/test")
If I run that section on the command line, it works:
$ typeset -A filelist
$ filelist["/home/reclusiarch/Documents/test"]=/home/reclusiarch/test
$ echo ${filelist["/home/reclusiarch/Documents/test"]}
/home/reclusiarch/test
Thanks for your help!!
Edit: I intially pared down the script to the piece of offending code but that might make it not run. Again, if you want to test it, you could run the bash command given. (The script ideally would reside in the user's $HOME directory).
Edit: Solved (Charles Duffy solved it) It was a simple mistake of forgetting which name was which.
Your declaration is:
typeset -A filelist
However, your usage is:
fileslist["$dirFrom"]="$dirTo"
fileslist is not filelist.

Distinguish different type of input (BASH)

I have a script that must be able to accept both by files and stdin on the first argument. Then if more or less than 1 arguments, reject them
The goal that I'm trying to accomplish is able to accpet using this format
./myscript myfile
AND
./myscript < myfile
What I have so far is
if [ "$#" -eq 1 ]; then #check argument
if [ -t 0 ]; then #check whether input from keyboard (read from github)
VAR=${1:-/dev/stdin} #get value to VAR
#then do stuff here!!
else #if not input from keyboard
VAR=$1
if [ ! -f "$VAR" ]; then #check whether file readable
echo "ERROR!"
else
#do stuff heree!!!
fi
fi
fi
The PROBLEM is when I tried to say
./myscript < myfile
it prints
ERROR!
I dont know whether this is the correct way to do this, I really appreciate for suggestion or the correct code for my problem. Thank you
#!/bin/bash
# if nothing passed in command line pass "/dev/stdin" to myself
# so all below code can be made branch-free
[[ ${#} -gt 0 ]] || set -- /dev/stdin
# loop through the command line arguments, treating them as file names
for f in "$#"; do
echo $f
[[ -r $f ]] && while read line; do echo 'echo:' $line; done < $f
done
Examples:
$ args.sh < input.txt
$ args.sh input.txt
$ cat input.txt | args.sh

bash- reading file from stdin and arguments

So I have googled this and thought I found the answers, but it still doesnt work for me.
The program computes the average and median of rows and columns in a file of numbers...
Using the file name works:
./stats -columns test_file
Using cat does not work
cat test_file | ./stats -columns
I am not sure why it doesnt work
#file name was given
if [[ $# -eq 2 ]]
then
fileName=$2
#file name was not given
elif [[ $# -eq 1 ]]
then
#file name comes from the user
fileName=/dev/stdin
#incorrect number of arguments
else
echo "Usage: stats {-rows|-cols} [file]" 1>&2
exit 1
fi
A very simple program that accepts piped input:
#!/bin/sh
stdin(){
while IFS= read -r i
do printf "%s" "$i"
done
}
stdin
Test is as follows:
echo "This is piped output" | stdin
To put that into a script / utility similar to the one in the question you might do this:
#!/bin/sh
stdin(){
while IFS= read -r i
do printf "%s" "$i"
done
}
rowbool=0
colbool=0
for i in $#
do case "$i" in
-rows) echo "rows set"
rowbool=1
shift
;;
-cols) echo "cols set"
colbool=1
shift
;;
esac
done
if [[ $# -gt 0 ]]
then
fileName=$1
fi
if [[ $# -eq 0 ]]
then fileName=$(stdin)
fi
echo "$fileName"

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