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48
votes
12answers
16k views

Get exit status of process that's piped to another

I have two processes foo and bar, connected with a pipe: $ foo | bar bar always exits 0; I'm interested in the exit code of foo. Is there any way to get at it?
2
votes
1answer
54 views

more command behavior

Someone can explain me about the more command? when I use it with || or with &&, it seems to have an exist status of true, even when the file is not found(Unlike the other commands). ...
7
votes
5answers
174 views

Can a program next in a pipeline see the exit code of the previous program?

I would like to make a pipeline of Bash scripts like this prog1 | prog2 such that prog2 can see the exit code of prog1 and act differently based on that information. Is this possible?
1
vote
1answer
24 views

How do I obtain the kill signal / message / reason within a script?

I am using the following trap: trap OnExit EXIT And in my OnExit function I would like to capture all the info I can on what happened so I can write it to a log file. Id like to know who, why, how, ...
0
votes
2answers
83 views

Exit the bash function, not the terminal

I have a bash script as below which installs zookeeper but only if not installed already. ##zookeper installZook(){ ZOOK_VERSION="3.4.5" ZOOK_TOOL="zookeeper-${ZOOK_VERSION}" ...
2
votes
1answer
30 views

What signal does X send to its clients when it receives SIGINT?

If I terminate the Xorg server with a SIGINT signal (eg. when I press Ctrl+C), what signal does it send to its clients?
1
vote
1answer
39 views

How can I return a specific error code at this point in my TCL script?

I have a TCL expect script that runs a scp command for uploading a config file to my DNS server: #!/usr/bin/expect -f set config "~/dnsmasq.conf" spawn /usr/bin/scp "$config" ...
2
votes
3answers
387 views

How to copy or read the return value (exit status) from AWK script into the shell script (bash) to be used in if statement to compare

I want to read the error codes or the exit status of awk script into shell to use in if condition to compare for error handling my shell script looks something like: My script: #!/bin/sh awk -v ...
1
vote
3answers
82 views

How do I shutdown the system after a particular process exits

I am downloading some software; I can see the pid of the download process with top. Let's say it's 1001. How can I make it so that my computer shuts down after process 1001 exits?
6
votes
1answer
106 views

How do I capture the exit code / handle errors correctly when using process substitution?

I have a script that parses file names into an array using the following method taken from a Q&A on SO: unset ARGS ARGID="1" while IFS= read -r -d $'\0' FILE; do ARGS[ARGID++]="$FILE" done ...
3
votes
1answer
256 views

Unable to get the right exit code from a script

I have a script which connects to a remote server via SFTP and get some file from there. My script goes like this: /usr/bin/sftp USER@remote.server.com <<EOF lcd /dir1/dir2/dir3 cd ...
2
votes
5answers
2k views

What does exit 99 means?

I'm new to Unix. Just want to know what is exit 99 and why would one use it and what are the significance uses of it. For example, I'm using exit 99.
3
votes
0answers
233 views

Proper usage of EXIT & ERR traps in bash scripts [closed]

I'm working on a bash script and as I've been going I've learned about traps, signals, function return codes and other such features I've not previously used. I may be thinking about things ...
1
vote
1answer
77 views

How to get exit code of a parallel process launched by xargs?

I'd made a script for launching parallel rsync process: #! /bin/bash LIST=$1 DEST_DIR=$2 RSYNC_OPTS=$3 #echo "rsyncing From=$SRC_DIR To=$DEST_DIR RSYNC_OPTS=$RSYNC_OPTS" echo $LIST|xargs -n1 -d, ...
2
votes
3answers
86 views

Get exit status of a process over SSH

Not sure how to google this (I tried with some things and didn't get much) or how this is even called. This is my typical workflow: SSH to a server run something there and leave it running in ...
1
vote
2answers
878 views

PHP exec command has the result 0 even if an error occurs

I have this PHP code: $execout=exec('ssh root@xxx.xxx.xxx.xx "sudo /etc/init.d/smokeping reload"',$output1,$result); if($result !=0){ echo"that can't reload"; } else{ echo "successfully ...
1
vote
1answer
977 views

How to exit out of the shell script successfully so that python subprocess think it is successfull exit? [closed]

Below is my shell script which simply execute a url like this http://example.com:8080/beat and parse the response and verify certain conditions on it. If that condition is met, then exit successfully ...
5
votes
3answers
992 views

reliable return code of background process

Let's assume the following piece of bash code: foo > logfile 2>&1 & foo_pid=$! while ps -p$foo_pid do ping -c 1 localhost done wait $foo_pid if [[ $? == 0 ]] then echo "foo ...
2
votes
2answers
116 views

Why does procmail send a copy of an inbound message to sender if it encounters an exit code?

I have a very simple procmail process that takes an inbound email and redirects it to a script: LOGFILE=/home/foo/procmail-log VERBOSE=yes MAILDIR=/var/spool/mail/foo DEFAULT=/var/spool/mail/foo ...
0
votes
2answers
143 views

How do I get the list of exit codes (and/or return codes) and meaning for a command/utility?

Is there a way I can do what stated in the title from the terminal commands, or will I have to look into the codes?
69
votes
4answers
1k views

Can I somehow add a “&& prog2” to an already running prog1?

Most shells provide functions like && and ; to chain the execution of commands in certain ways. But what if a command is already running, can I still somehow add another command to be executed ...
16
votes
9answers
1k views

How to make sure that a command is not interrupted, even if terminal is closed? [duplicate]

In Linux. Say I want to run a command and it takes too long. I just want to ensure it's done. How?
3
votes
2answers
825 views

test if return true if grep on output has string in one line

I just want to return true or false if a service is running. Here is where I'm at, not first try or last but current at writing: service iptables status | grep -qi "not running" The sdtout for ...
0
votes
2answers
2k views

Expect script within bash & exit codes

I have a bash script that calls an expect script. The expect script has several conditions. It ssh's into a box and executes a command, and there are different possible errors that could happen which ...
0
votes
1answer
123 views

if env variable exists then exit out of script

#!/bin/bash if [[ -n "$MYVAR" ]]; then exit; fi # otherwise the rest of the script continues... I'm trying to exit out of a shell script if a certain ENV variable is 0. The script above does not ...
2
votes
2answers
530 views

Busybox ash script does not exit cleanly after executing cat; unable to get exit code

Consider the following script wrapcat.sh (a wrapper for cat) for illustrative purposes. It is run with busybox (ash) in an embedded Linux 2.6 box. #!/bin/sh cat $1 Under certain circumstances, this ...
2
votes
2answers
747 views

Removing zombie process from the process table

Can somebody please explain when parent process receives the exit status of a dead child process via wait, who actually reallocates the memory of the child process and removes it from the process ...
3
votes
2answers
291 views

What is “Exit 2” from finished background job status?

I have an exercise to put in a file some data (*conf from some directories) and need to do this in background. I did it and I am wondering what is the meaning of output messages: [A@localhost tests]$ ...
0
votes
2answers
228 views

Test if number from range <0,infinity)

I have a problem If [[ * ]] then continue else exit 1 fi I want to test that the argument to my switch (for example -d 3) is a valid positive decimal integer number (a sequence of one or more of ...
2
votes
1answer
133 views

How to have a bash script perform a specific action on errors of _each_ command?

Similarly to set -e performs an exit on "uncaught" $? != 0, I'd like to have this event trigger the execution of another command, e.g. a logger call. How can this be done?
3
votes
1answer
421 views

How to trick an init script into returning 0

I have a init script which is poorly designed because it does not conform to the Linux Standard Base Specifications The following should have an exit code of 0 if running, and 3 if not running ...
12
votes
3answers
1k views

Wait command usage in Linux?

#!/bin/bash function back() { sleep $1 exit $2 } back $1 $2 & b=$! if `wait $!`;then echo success else echo failure fi bash-3.00# ./back 300 0 failure bash-3.00# ./back 300 1 ...
8
votes
4answers
2k views

Why should a child of a vfork or fork call _exit() instead of exit()?

From the man page of vfork(): vfork() differs from fork() in that the parent is suspended until the child makes a call to execve(2) or _exit(2). The child shares all memory with its ...
14
votes
2answers
534 views

Why does `exit &` not work?

I don't understand why exit & does not work. Why does it not?
5
votes
1answer
263 views

Return value of a process and comparison of the number

I have a val.py python script that returns a negative number. import sys sys.exit(-1234) When I run this bash script, I get the value $? as return value of 46 (not -1234). Even when I tried to ...
1
vote
0answers
1k views

Using sshpass, return code (exit status) differs for reasons unknown using valid commands

There are a few things going on here but I think ultimately, either CLish or SSH is returning an exit code that is messing up my work flow. I'm attempting to connect to a remote machine (CLish shell) ...
0
votes
2answers
192 views

Unix command to exit from command prompt

How can I exit from command prompt from shell file? shell file contains : if(); then // some unix code here else // want to exit from cmd prompt or Kill current cmd prompt fi can any knows @ it?
0
votes
1answer
657 views

ksh - map Ctrl-D to exit shell

I would like to know how we can map the keys Ctrl-D in ksh to exit the shell as it does in bash shell. Not much familiar with key binding in ksh. Edit My comments are after the <!-- string ...
5
votes
3answers
510 views

bash -e exits when let or expr evaluates to 0

I have a bash script that sets -e so the script will exit on any exit status != 0. I'm trying to do some basic shell arithmetic assigned to variables and sometimes the expression equals 0 which ...
2
votes
1answer
284 views

Exit status ($?) of 148 upon Ctrl+Z

I just customized my .bashrc to include the exit status of the last command, so I get fancy prompts like ☑ larsmans@host:~$ and I no longer have to re-run commands to see their exit status because ...
3
votes
1answer
1k views

Why won't my bash script exit after execution?

I compiled a short bash one-liner to focus a running application or launch it if it isn't running: #!/bin/bash #intellilaunch.sh wmctrl -a $1 || $1 & disown exit 1 The command exits perfectly ...
2
votes
2answers
107 views

Are any files loaded when a terminal session terminates?

I know that .profile / .bash_profile are loaded when a terminal session is started, either through local machine or SSH. Are there any files that are loaded/called when the session terminates? ...
6
votes
6answers
17k views

exit out of all SSH connections in one command and close PuTTY

Is there a way to back out of all SSH connections and close PuTTY in "one shot"? I work in Windows 7 and use PuTTY to SSH to various Linux hosts. An example of the way I find myself working: SSH to ...
3
votes
3answers
864 views

What does exit do in an if block in a shell script?

I have a question regarding unix shell script. Say if you do exit 1 in inner if: will it exit or will it still execute the outer if? The following is a dummy example. if [ "$PASSWORD" == ...
1
vote
2answers
502 views

Negate exit code without using shell features

Is there any standard command that will negate the the exit code of another command provided as an argument without using shell features, or starting a shell? I have a program that does something ...
3
votes
2answers
324 views

How to write an abort-on-error script without adding `|| exit $?` to every line?

I'm writing a bash script that should exit the error code of the last failed command and not continue execution. This can be achieved by adding a || exit $? everywhere, but is there an easier way, ...
5
votes
1answer
220 views

How does sh -e interact with &?

I'm using sh (dash) on Ubuntu (lucid) and the manpage has this to say about -e: -e errexit If not interactive, exit immediately if any untested command fails. ...
6
votes
3answers
2k views

exit shell script from a subshell

Consider this snippet: stop () { echo "${1}" 1>&2 exit 1 } func () { if false; then echo "foo" else stop "something went wrong" fi } Normally when func ...
2
votes
3answers
364 views

Return value of commands when using stdin?

Imaging I am executing the following command: echo "root:mypass" | chpasswd How can I get the return code / error code returned by chpasswd? Is that possible in this case at all? I tried RET = ...
3
votes
1answer
442 views

wait does not wait

If i have a file called myprogram containing sleep 200 date Run this in the background: $ sh myprogram & i want to know when myprogram has completed by using wait command $ cat >notify ...