Something similar to this maybe:
#! /bin/bash
echo What is your name?
read name | cat > ~/Documents/file.txt
if [[ $name==Bob ]]
echo something
fi
The command creates an empty file on manjaro mint.
Your problem is that read doesn't create any output.
And you have a syntax error further down the line, it would be a good idea to put your script(s) through shellcheck.
#! /bin/bash
echo What is your name?
read -r name
echo "$name" > ~/Documents/file.txt
if [[ "$name" == "Bob" ]]; then
echo something
fi
Related
I'm new on bash. I want to write a script which will run iwconfig command the output should show me my wlan* mode is Managed or Monitor?
I had tried this like following but it is not working and runs the command output. I just need to echo which mode is it.
IWCONFIG_LOG="$(iwconfig)"
if [[ "$IWCONFIG_LOG" == *Mode:Managed* ]]; then
echo "Managed"
elif [[ "$IWCONFIG_LOG" == *Mode:Monitor* ]]; then
echo "Monitor Mode"
fi
Looks like you want to use Bash (not sh) in order to get this accomplish.
So, try this:
#!/bin/bash
IWCONFIG_LOG="$((iwconfig | grep Mode) 2> /dev/null)"
if [[ $IWCONFIG_LOG == *"Mode:Managed"* ]]; then
echo "Managed"
elif [[ $IWCONFIG_LOG == *"Mode:Monitor"* ]]; then
echo "Monitor Mode"
fi
Save it as a file and chmod 755 it to make it executable or execute it using "bash" instead "sh".
There are several modes, not only Managed or Monitor, so seems you only want to detect one of these two.
To see all available modes read man iwconfig
Since iwconfig writes also to standard error:
if [[ $(iwconfig 2>/dev/null | grep "Managed") ]]; then
echo "Managed"
else
echo "Monitor"
fi
or, as pointed out by #choroba in comments:
if iwconfig 2>/dev/null | grep -q Managed ; then
echo "Managed"
else
echo "Monitor"
fi
Please explain to me why the very last echo statement is blank? I expect that XCODE is incremented in the while loop to a value of 1:
#!/bin/bash
OUTPUT="name1 ip ip status" # normally output of another command with multi line output
if [ -z "$OUTPUT" ]
then
echo "Status WARN: No messages from SMcli"
exit $STATE_WARNING
else
echo "$OUTPUT"|while read NAME IP1 IP2 STATUS
do
if [ "$STATUS" != "Optimal" ]
then
echo "CRIT: $NAME - $STATUS"
echo $((++XCODE))
else
echo "OK: $NAME - $STATUS"
fi
done
fi
echo $XCODE
I've tried using the following statement instead of the ++XCODE method
XCODE=`expr $XCODE + 1`
and it too won't print outside of the while statement. I think I'm missing something about variable scope here, but the ol' man page isn't showing it to me.
Because you're piping into the while loop, a sub-shell is created to run the while loop.
Now this child process has its own copy of the environment and can't pass any
variables back to its parent (as in any unix process).
Therefore you'll need to restructure so that you're not piping into the loop.
Alternatively you could run in a function, for example, and echo the value you
want returned from the sub-process.
http://tldp.org/LDP/abs/html/subshells.html#SUBSHELL
The problem is that processes put together with a pipe are executed in subshells (and therefore have their own environment). Whatever happens within the while does not affect anything outside of the pipe.
Your specific example can be solved by rewriting the pipe to
while ... do ... done <<< "$OUTPUT"
or perhaps
while ... do ... done < <(echo "$OUTPUT")
This should work as well (because echo and while are in same subshell):
#!/bin/bash
cat /tmp/randomFile | (while read line
do
LINE="$LINE $line"
done && echo $LINE )
One more option:
#!/bin/bash
cat /some/file | while read line
do
var="abc"
echo $var | xsel -i -p # redirect stdin to the X primary selection
done
var=$(xsel -o -p) # redirect back to stdout
echo $var
EDIT:
Here, xsel is a requirement (install it).
Alternatively, you can use xclip:
xclip -i -selection clipboard
instead of
xsel -i -p
I got around this when I was making my own little du:
ls -l | sed '/total/d ; s/ */\t/g' | cut -f 5 |
( SUM=0; while read SIZE; do SUM=$(($SUM+$SIZE)); done; echo "$(($SUM/1024/1024/1024))GB" )
The point is that I make a subshell with ( ) containing my SUM variable and the while, but I pipe into the whole ( ) instead of into the while itself, which avoids the gotcha.
#!/bin/bash
OUTPUT="name1 ip ip status"
+export XCODE=0;
if [ -z "$OUTPUT" ]
----
echo "CRIT: $NAME - $STATUS"
- echo $((++XCODE))
+ export XCODE=$(( $XCODE + 1 ))
else
echo $XCODE
see if those changes help
Another option is to output the results into a file from the subshell and then read it in the parent shell. something like
#!/bin/bash
EXPORTFILE=/tmp/exportfile${RANDOM}
cat /tmp/randomFile | while read line
do
LINE="$LINE $line"
echo $LINE > $EXPORTFILE
done
LINE=$(cat $EXPORTFILE)
readLBL.sh
#!/bin/bash
while IFS='' read -r line || [[ -n "$line" ]]; do
echo "Text read from file: $line"
done < "$1"
When I run this shell script in Terminal and I have to insert file name for run it
Example :
./readLBL.sh science.txt
output :
58050364;Tom Jones
58050365;Marry Jane
how can i keep "science.txt" into some variable like a = "science.txt"
Use $1 as this is the argument you are already using to read the file in the first instance.
#!/bin/bash
while IFS='' read -r line || [[ -n "$line" ]]; do
echo "Text read from file $1: $line"
done < "$1"
Running this gives the following:
$ ./readLBL.sh science.txt
Text read from file science.txt: 58050364;Tom Jones
Text read from file science.txt: 58050365;Marry Jane
a="science.txt"
from the Linux command line, will set $a equal to science.txt
If you want this permanent, you could perhaps add it to the bottom of one of your linux profiles. For example add it to the bottom of ~/.bashrc
What is the difference between -f and -e in shell?
I know that
-e : To check if the file name exists
-f : To check if a file exists
But, what is difference among them?
EDIT:
I am looking in particular at this snippet of code:
if [ -e test.sh ]; then
echo "Yes";
else
echo "No";
fi
if [ -f test.sh ]; then
echo "Yes";
else
echo "No";
fi
Both print Yes.
-f is like -e but it additionally checks that the name refers to a plain file (as opposed to a directory, socket, etc.).
See the description of st_mode / S_IFMT in man 2 stat for a list of possible file types.
I am trying to write a bash/shell script to zip up a specific folder and ignore certain sub-dirs in that folder.
This is the folder I am trying to zip "sync_test5":
My bash script generates an ignore list (based on) and calls the zip function like this:
#!/bin/bash
SYNC_WEB_ROOT_BASE_DIR="/home/www-data/public_html"
SYNC_WEB_ROOT_BACKUP_DIR="sync_test5"
SYNC_WEB_ROOT_IGNORE_DIR="dir_to_ignore dir2_to_ignore"
ignorelist=""
if [ "$SYNC_WEB_ROOT_IGNORE_DIR" != "" ];
then
for ignoredir in $SYNC_WEB_ROOT_IGNORE_DIR
do
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/**\*"
done
fi
FILE="$SYNC_BACKUP_DIR/$DATETIMENOW.website.zip"
cd $SYNC_WEB_ROOT_BASE_DIR;
zip -r $FILE $SYNC_WEB_ROOT_BACKUP_DIR -x $ignorelist >/dev/null
echo "Done"
Now this script runs without error, however it is not ignoring/excluding the dirs I've specified.
So, I had the shell script output the command it tried to run, which was:
zip -r 12-08-2014_072810.website.zip sync_test5 -x sync_test5/dir_to_ignore/**\* sync_test5/dir2_to_ignore/**\*
Now If I run the above command directly in putty like this, it works:
So, why doesn't my shell script exclude working as intended? the command that is being executed is identical (in shell and putty directly).
Because backslash quotings in a variable after word splitting are not evaluated.
If you have a='123\4', echo $a would give
123\4
But if you do it directly like echo 123\4, you'd get
1234
Clearly the arguments you pass with the variable and without the variables are different.
You probably just meant to not quote your argument with backslash:
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/***"
Btw, what actual works is a non-evaluated glob pattern:
zip -r 12-08-2014_072810.website.zip sync_test5 -x 'sync_test5/dir_to_ignore/***' 'sync_test5/dir2_to_ignore/***'
You can verify this with
echo zip -r 12-08-2014_072810.website.zip sync_test5 -x sync_test5/dir_to_ignore/**\* sync_test5/dir2_to_ignore/**\*
And this is my suggestion:
#!/bin/bash
SYNC_WEB_ROOT_BASE_DIR="/home/www-data/public_html"
SYNC_WEB_ROOT_BACKUP_DIR="sync_test5"
SYNC_WEB_ROOT_IGNORE_DIR=("dir_to_ignore" "dir2_to_ignore")
IGNORE_LIST=()
if [[ -n $SYNC_WEB_ROOT_IGNORE_DIR ]]; then
for IGNORE_DIR in "${SYNC_WEB_ROOT_IGNORE_DIR[#]}"; do
IGNORE_LIST+=("$SYNC_WEB_ROOT_BACKUP_DIR/$IGNORE_DIR/***") ## "$SYNC_WEB_ROOT_BACKUP_DIR/$IGNORE_DIR/*" perhaps is enough?
done
fi
FILE="$SYNC_BACKUP_DIR/$DATETIMENOW.website.zip" ## Where is $SYNC_BACKUP_DIR set?
cd "$SYNC_WEB_ROOT_BASE_DIR";
zip -r "$FILE" "$SYNC_WEB_ROOT_BACKUP_DIR" -x "${IGNORE_LIST[#]}" >/dev/null
echo "Done"
This is what I ended up with:
#!/bin/bash
# This script zips a directory, excluding specified files, types and subdirectories.
# while zipping the directory it excludes hidden directories and certain file types
[[ "`/usr/bin/tty`" == "not a tty" ]] && . ~/.bash_profile
DIRECTORY=$(cd `dirname $0` && pwd)
if [[ -z $1 ]]; then
echo "Usage: managed_directory_compressor /your-directory/ zip-file-name"
else
DIRECTORY_TO_COMPRESS=${1%/}
ZIPPED_FILE="$2.zip"
COMPRESS_IGNORE_FILE=("\.git" "*.zip" "*.csv" "*.json" "gulpfile.js" "*.rb" "*.bak" "*.swp" "*.back" "*.merge" "*.txt" "*.sh" "bower_components" "node_modules")
COMPRESS_IGNORE_DIR=("bower_components" "node_modules")
IGNORE_LIST=("*/\.*" "\.* "\/\.*"")
if [[ -n $COMPRESS_IGNORE_FILE ]]; then
for IGNORE_FILES in "${COMPRESS_IGNORE_FILE[#]}"; do
IGNORE_LIST+=("$DIRECTORY_TO_COMPRESS/$IGNORE_FILES/*")
done
for IGNORE_DIR in "${COMPRESS_IGNORE_DIR[#]}"; do
IGNORE_LIST+=("$DIRECTORY_TO_COMPRESS/$IGNORE_DIR/")
done
fi
zip -r "$ZIPPED_FILE" "$DIRECTORY_TO_COMPRESS" -x "${IGNORE_LIST[#]}" # >/dev/null
# echo zip -r "$ZIPPED_FILE" "$DIRECTORY_TO_COMPRESS" -x "${IGNORE_LIST[#]}" # >/dev/null
echo $DIRECTORY_TO_COMPRESS "compressed as" $ZIPPED_FILE.
fi
After a few trial and error, I have managed to fix this problem by changing this line:
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/**\*"
to:
ignorelist="$ignorelist $SYNC_WEB_ROOT_BACKUP_DIR/$ignoredir/***"
Not sure why this worked, but it does :)