Questions tagged [exec]
The exec() family of functions replaces the current process image with a new process image, retaining the pid and pipes of the old process. This tag is also used for the shell built-in which can be used to replace the current shell with a program or various redirection-related stuff.
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How is this exec command supposed to work in this context?
I'm working through a textbook on UNIX system administration. Chapter 3 of "Unix Third Edition" by a Syed Mansoor.
Chapter 13 has the following example of exec usage which is straightforward ...
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1
answer
51
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how to bring exec $@ process in foreground
I want to know how docker entry point process which has started with exec $@ and has PID 1 how to bring that in foreground
I tried exec $@ & but its not working,
My use case:
I want to terminate ...
- 55
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2
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missing argument to `-exec' error when executing Shell script but runs fine on command lines
I have this Shell script here:
###
# Create a folder dynamically
mkdir archived_PA_"$(date -d "6 months ago - 1 day" +%Y-%m-%d)"_"$(date -d "1 day ago" +%Y-%m-%d)&...
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How to load android binaries in Debian environment?
I am trying to run adbd from within a chrooted environment. I can run it fine with Android's LD_LIBRARY_PATH=$PWD ./linker64 $PWD/adbd.
When I try to run ./adbd I get:
bash: ./adbd: cannot execute: ...
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Why does subcommand take the PID of parent when I don't use exec [duplicate]
I executed bash -c "ps && ps" and got the following output:
PID TTY TIME CMD
25544 pts/0 00:00:00 bash
26562 pts/0 00:00:00 bash
26563 pts/0 00:00:00 ps
PID TTY ...
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46
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How to display file and folder properties from search
I thought this would be easy and there are a lot of somewhat close threads on the internet, but nothing quite right.
I want to use fd (simple find command) to display just file name and file size (...
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2
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148
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Capture and redirect stdin (user input) for runtime of script
I can redirect the stdout/stderr of everything in a script like this:
#!/bin/bash
exec > stdout_file
echo example
But now I want the stdin of the whole script to be written into a file. I tried it ...
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1
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Log all commands executed regardless of shell?
Suppose a user runs the following command:
zcat file.gz | grep something | gzip > grepped.gz
I'm looking for a kernel feature (a BPF filter perhaps?) that would note all of the execves, chain ...
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1
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48
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Why 'helix-23.03-aarch64.AppImage' [in debian on x86_64 in Macbook Pro] is giving 'Exec format error'?
It is on debian on x86_64
me@debian:~/bin$ chmod a+x helix-23.03-aarch64.AppImage
me@debian:~/bin$ ./helix-23.03-aarch64.AppImage
/tmp/.mount_helix-RyzFyw/AppRun: 4: exec: /tmp/.mount_helix-RyzFyw/usr/...
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bash -c "exec -a myProcessName ./script.sh &" doesn't send that script into backgound
From a bash script, I need to start three processes and put to each of these processes a name, in order to be able to stop them in a later stop command.
# Démarrer les applications eco emploi : ...
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2
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1
answer
154
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Why does the provided command as a parameter not run in a loop in my script?
I made a simple script that executed a command every minute:
#!/usr/bin/env sh
while true; do
exec "$@"
sleep 60
done
The idea is to make it as a Docker entrypoint that will allow ...
- 1,011
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1
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314
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Does running exec command preserves environment variables of the calling shell? If so, why?
From my understanding exec command replaces the calling shell program with the command without forking a child process. Also if I understand correctly exported variables are the ones that are passed ...
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1
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152
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Help with -maxdepth in 'find -exec mv' command line
I'm working on a sorting/filtering cron script to process incoming files based on a set of constant strings (logfile, history, dataset, etc). The files to be sorted all sit under a common folder, some ...
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239
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"exec" is exiting the script and not proceeding to next step
We are trying to capture return code of exec command but once the command is executed the script is getting exit without proceeding to next lines.
exec /bin/sh -c $command > log.txt
rc=$?
if [ $rc -...
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How to set the Exec when bash command is too long?
The desktop file works fine:
[Desktop Entry]
Type=Action
Name=unrar zip or rar file
Profiles=unrar
[X-Action-Profile unrar]
MimeTypes=inode/directory
Exec=bash -c "unar /home/test.rar -o /tmp;...
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2
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Redirecting stderr to temporary fd in a Bash script
I see that many questions have been asked and answered on SE about redirections in Bash using exec, but none seem to answer my question.
What I'm trying to accomplish is redirect all output to stderr ...
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2
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1
answer
48
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How do I insert my own lib to other binaries in Linux?
My goal is developing a tool for educational purposes which logs commands on a system. Until now have found primitive ways to do this but all these ways can be easily bypassed so I had this idea to ...
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4
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286
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execute a command recursively on the files of a folder in the matching location, not in the original one
I want to recursively convert files from .docx to .doc in a folder. The problem is that all the output files are created in the folder where I run the following command, not in the location of the ...
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246
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Is it possible to load up a binary into ram, without executing it?
Like I will use google chrome whenever I use linux (most probably) But I don't want it to auto start when ever I open it. I could open it manually, but I have HDD so it is pain to load for the first ...
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3
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1
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376
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Signal handling in shell script with exec and pipe to filter output with grep
I'm deploying a containerized application which outputs an enormous amount of useless messages on startup (the same message for about a million times, without any variation). The message cannot be ...
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Need to capture exit code of pylint command using find in Github actions
I am trying to implement a python linter using pylint. But I am getting the score of each python file and also displaying the suggestion to improve the score but I am also looking to terminate the ...
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3
answers
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How to print to stdout after exec >/dev/null
In a script, I have a long list of commands that print to stdout. I want to hide all output. So instead of redirecting each command, I put
exec >/dev/null
at the beginning.
What options do I have ...
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0
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36
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Why does the exec redirection disturb / interrupt a pipe to jq? [duplicate]
This is the reduced version of my script:
# parse json
echo '[{"foo":"bar"}]' | jq
# log output to file and stdout
exec &> >(tee -a "/tmp/test.log")
# parse ...
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1
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129
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Why basename don't work here [duplicate]
Why when I do this (I know, it's stupid) it returns the full path, not only the filename as expected?
ls -l | awk '{print $9}' | xargs -I% find ./my_dir -type f -name "%" -exec echo $(...
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704
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The total size of the argument list and exported variables exceeds the OS limit of 1MB
I was doing a grid search for some scientific computing project, and got a bunch of log files with parameters embedded in the filenames.
$ ls -l | wc -l
38210
$ ls -l | tail
-rw-rw-r-- 1 qys ...
- 369
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1
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138
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Working with file descriptors in the (bash) shell?
I came across the following set of shell commands for reading and writing to serial ports, from this thread:
stty -speed 19200 < /dev/ttyS0 # sets the speed of the port
exec 99<>/dev/ttyS0 (...
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What happens to the file structs of processes after execve
If I understand the man pages correctly, the fd table of a process that forks and execves are copied to the the child process and survive the execve. On the other hand, any other memory mapping is ...
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118
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exec terminate command by the space in single quotes
I have a simple bash script goes like
#!/bin/bash
set -e
SPARK_CONF="--master ... \
...
--conf spark.driver.extraJavaOptions='-verbose:gc -XX:+PrintGCDetails -XX:+PrintGCDateStamps' \
--conf ....&...
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pass output as grep pattern [duplicate]
I wish to pass each line of a file as a grep pattern to be searched in data.txt file.
Thus, i need cat allsearchstrings.txt | grep <should be lines of allsearchstrings.txt> data.txt
cat ...
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763
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`exec env` vs `env`
Both exec and env don't fork, see the following example:
docker run --rm -it ubuntu:18.04 sh -c 'exec sleep 1 & ps -Ho pid,ppid,cmd'
PID PPID CMD
1 0 sh -c exec sleep 1 & ps -Ho ...
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1
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376
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Output to variable or file using (find with -exec and shred)
I have a find command that I exec to shred and it works great; however, I need to capture the output of this and pass to a variable or a file. I have tried so many iterations of the below commands, ...
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How to launch application with rofi using i3wm's exec?
I had this issue and now I know how to solve it. I need to launch applications with i3wm's exec command.
ButI use rofi as launchmenu and I have no idea how to make it lauch applications with i3wm's ...
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670
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Delete all files in directories tomcat_*/temp on each application restart
We do have an operation script to stop, restart and start tomcat services. I am asked to make changes in the operation script so when starting tomcat with operation_script.sh, All files in directories ...
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2
answers
3k
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What does `exec 6>&1` or similar do?
I'm migrating some software from Unix to Linux.
I have the following script; it is a trigger of a file transfer.
What do the exec commands do?
Will they work also on Linux?
#!/bin/bash
flog=/mypath/...
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0
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1k
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How is i3 window manager started by startx in Ubuntu (so that I can configure what display it appears on)?
I want to set up i3 automatically start on a specific one of my three screens (all connected to one Nvidia card). This has proved more difficult than expected.
My first choice was to just set that ...
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1
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496
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How to increment COUNTER in -exec script?
Context: zsh Catalina MacOS:
The executable script BatesStamp engages imagemagick to stamp a number to a jpg file:
# BatesStamp: OVERWRITES and stamps ONE file with COUNTER (upper left corner)
# ...
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2
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187
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exec vscode not redirecting output to /dev/null
I have the following bash script:
exec '/mnt/c/Users/WindowsUserName/AppData/Local/Programs/Microsoft VS Code/Code.exe' $@ &>/dev/null &
When I run the script I get
➜ ~ ./code foo.js
➜ ~
...
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1
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How does exec > work in AWS EC2 user data?
I was writing a Terraform module for AWS EC2 that involved executing a bash in the user data section. While I was developing I had an issue in the script I wrote but neither AWS nor Terraform provided ...
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exec command not found error in Linux
below commands are giving output and exiting the terminal
exec sleep 60
exec pwd
below commands throws error. please advise on the exec behaviour
$ exec test1.sh
-bash: exec: test1.sh: not found
$ ...
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343
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How to pass grep result to a varible so i can use it with exec tar command?
I am trying to compress all folder in dir based on some regex so I used grep to filter out the output now i need to use tar and folder name.
For example I want to .tar.gz each top level directory to ...
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312
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php exec/shell_exec behavior CLI vs CGI
I am trying to use php to run some system commands and am getting a behaviour that I don't fully understand. If the php script is run from the command line I get the results I expect. But running it ...
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0
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196
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Exec Not Updating Values from Certain Bash Functions and Variables When Prepending Script Output
I am logging messages in Bash where I add some useful information to the log message to help provide context. However, in the final output most of my variables and functions appear to only use their ...
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1
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163
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Output of this command Linux [closed]
Please do anyone has an idea about the output of this command , I have googled a lot about it but I can't find anything useful
find . -type f -exec grep -H PATH {} \;
Thanks in advance
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OpenBSD 6.9 - ENOMEM error on execve (execvp)
I've compiled a program on OpenBSD 6.9 and when I execute the program, I get an enomem error related specifically to execvp which the man pages say is a font-end for execve.
The execve man page ...
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process hangs after redirecting stderr using exec
I want to redirect stdout and stderr to 2 pipes one for each
to create the pipes I used:
mkfifo -m 0666 /var/run/log_stdout.pipe
mkfifo -m 0666 /var/run/log_stderr.pipe
and it works fine, but ...
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279
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ip netns exec cannot start ONLY mate-terminal and gnome-terminal?
I am using the newns script from here:
https://superuser.com/questions/983727/route-only-specific-traffic-through-vpn
... except on this system:
$ mate-about -v
MATE Desktop Environment 1.24.0
$ cat /...
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2
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Why does exec print its output after the program exits?
I'm writing a program to pipe one command to another. Inputs will be from the command line:
$ ./a.out ls '|' wc
c2 PID 6804
c1 PID 6803
PARENT PID 6802
$ 2 2 17
Why does the output ...
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2
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64
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How to delete ALL directories but NOT files from another location in execv? [closed]
Let's say I'm at the home directory and I have a directory called 'Apple' that has 2 directories (let's say I don't know their names) with contents in them and several files. I open my terminal in ...
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1
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792
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Why is 'ls' being created by execve() call and not fork()
From my understanding whenever you type a command such as 'ls' in your shell, the parent process which is my shell duplicates itself using fork() system call and then uses the exec() system call to ...
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1
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315
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How can I redirect all output of a script to a file and replace passwords?
I'm running a ksh script on AIX 7.2.
In debug mode I want to redirect all the script does to a brkpt-file.
The script also makes logins to another application and therefore uses a password (let's say &...
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