There's an issue I am facing with the following command.
Output does not seem to be suppressed, and I keep getting 100s of lines printed to the terminal.
#!/bin/sh
n=0
until [[ $n -ge 1000 ]]
do
/usr/ud/runupdate $1 &>/dev/null && break
n=$[$n+1]
sleep 2
done
Are there any other things I can do to suppress output?
Related
Lets Say I have multiple scripts which need to invoke sequentially for the job.
These scripts has long and lengthy output this is my bash script,
How to avoid that but still can understand that the process is running.
Here is an example,
#!/bin/bash
echo "Script to prepare Final BUILD"
rm -vf module1.out
module1_build_script.sh #FIXME: This scripts outputs 10000 lines
#module1_build_script.sh &> /dev/null #Not interested as this makes difficult if the process hangs or running.
if [ ! -f ./out/module1.out ];then
echo "Module 1 build failed"
exit 1
fi
.
.
.
rm -vf module1.out
module4_build_script.sh # This scripts outputs 5000 lines
if [ ! -f ./out/module4.out ];then
echo "Module 4 build failed"
exit 4
fi
Now I am expecting some code gives me effect like below output as one liner without scroll
example: module1_build_script.sh | "magical code here" #FIXME:
Like below output
user#bash#./myscript
#-------content of myscript ---------------
#!/bin/bash
while (( i < 10))
do
echo -en "\r Process is running...$i"
sleep 0.5
((i++))
done
#------------------------------------------
So I'm trying to check for the output of a command, but I also want to be able display the output directly in the terminal.
#!/bin/bash
while :
do
OUT=$(streamlink -o "$NAME" "$STREAM" best)
echo "$OUT"
if [[ $OUT == *"No playable streams"* ]]; then
echo "Delaying!"
sleep 15s
fi
done
This is what I tried to do.
The code checks if the output of a command contains that error substring, if so it'd add a delay. It works well on that part.
But it doesn't work well when the command is actually successfully downloading a file as it won't perform that echo until it is finished with the download (which would take hours). So until then I have no way of personally checking the output of the command
Plus the output of this particular command displays and updates the speed and filesize in real-time, something echo wouldn't be able to replicate.
So is there a way to be able to display the output of a command in real-time, while also command substituting them in order to check the output for substrings after the command is finished?
Use a temporary file:
TEMP=$(mktemp) || exit 1
while true
do
streamlink -o "$NAME" "$STREAM" best |& tee "$TEMP"
OUT=$( cat "$TEMP" )
#echo "$OUT" # not longer needed
if [[ $OUT == *"No playable streams"* ]]; then
echo "Delaying!"
sleep 15s
fi
done
# not really needed here because of endless loop
rm -f "$TEMP"
I've got the following code in my shell script:
SERVER=`ps -ef | grep -v grep | grep -c sof2ded`
if ["$SERVER" != "0"]; then
echo "Already Running, exiting"
exit
else
echo "Starting up the server..."
cd /home/sof2/
/home/sof2/crons/start.sh > /dev/null 2>&1
fi
I did chmod a+x status.sh
Now I try to run the script but it's returning this error:
./status.sh: line 5: [1: command not found
Starting up the server...
Any help would be greatly appreciated.
Could you please try changing a few things in your script as follows and let me know if that helps you?(changed back-tick to $ and changed [ to [[ in code)
SERVER=$(ps -ef | grep -v grep | grep -c sof2ded)
if [[ "$SERVER" -eq 0 ]]; then
echo "Already Running, exiting"
exit
else
echo "Starting up the server..."
cd /home/sof2/
/home/sof2/crons/start.sh > /dev/null 2>&1
fi
The problem is with the test command. "But", I hear you say, "I am not using the test command". Yes you are, it is also known as [.
if statement syntax is if command. The brackets are not part of if syntax.
Commands have arguments separated (tokenized) by whitespace, so:
[ "$SERVER" != "0" ]
The whitespace is needed because the command is [ and then there are 4 arguments passed to it (the last one must be ]).
A more robust way of comparing numerics is to use double parentheses,
(( SERVER == 0 ))
Notice that you don't need the $ or the quotes around SERVER. Also the spacing is less important, but useful for readability.
[[ is used for comparing text patterns.
As a comment, backticks ` ` are considered deprecated because they are difficult to read, they are replaced with $( ... ).
i have written a shell scripts which runs crontab - l command
To make it more easy to use i have also given the user an ability to pass a command line argument to the script which will act like a pattern input for the grep command, so that the user can filter out all the stuffs which he/she doesn't need to see.
here's the script:-
1 #!/bin/bash
2 if [[ $1 == "" ]]; then
3 echo -e "No Argument passed:- Showing default crontab\n"
4 command=$(crontab -l 2>&1)
5 echo "$command"
6 else
7 rc=$?
8 command=$(crontab -l | grep -- "$1" 2>&1)
9 echo "$command"
10 if [[ $rc != 0 ]] ; then
11 echo -e "grep command on crontab -l was not successful"
12 fi
13 fi
this is how i run it
$ ./DisplayCrontab.sh
Now if i don't pass any command line argument it'll show me the complete crontab
If i pass any garbage pattern which doesn't exists in the crontab it'll show me the following message :-
grep command on crontab -l was not successful
But even if i pass a pattern which does exist in a couple of lines in crontab, i'm getting this kind of output:-
#matching lines
#matching lines
#matching lines
grep command on crontab -l was not successful
Why am i getting grep command not successful at the bottom?, how can i get rid of it?
Is there anything wrong with the script?
You're capturing the exit code before the execution, should be:
command=$(crontab -l | grep -- "$1" 2>&1)
rc=$?
To test this code use numeric operators:
[[ $rc -ne 0 ]]
Grep man:
Normally, the exit status is 0 if selected lines are found and
1 otherwise. But the exit status is 2 if an error occurred
So i am writing a script to call a process 365 times and they should run in 10 batches, so this is something i wrote but there are multiple issues -
1. the log message is not getting written to the log file, i see the error message in err file
2. there is this "Command not found" error I keep getting from the script for the line process.
3. even if the command doesnt succeed, still it doesn't print FAIL but prints success
#!/bin/bash
set -m
FAIL=0
for i in {1..10}
do
waitPIDS=()
j=$i
while [ $j -lt 366 ]; do
exec 1>logfile
exec 2>errorfile
`process $j &`
waitPIDS[${#waitPIDS[#]}]=$!
j=$[$j+1]
done
for jpid in "${waitPIDS[#]}"
do
echo $jpid
wait $jpid
if [[ $? != 0 ]] ; then
echo "fail"
else
echo "success"
fi
done
done
What is wrong with it ?
thanks!
At the very least, this line:
`process $j &`
Shouldn't have any backticks in it. You probably just want:
process $j &
Besides that, you're overwriting your log files instead of appending to them; is that intended?