The concurrency tag has no wiki summary.
3
votes
1answer
56 views
Edge cases in filesystem operations during backup and file copy
I have a question about file access in Linux that I cannot sum it up completely.
Consider that I have a home directory that I backup it using rsync triggered via cron. My home directory is on an EXT4 ...
2
votes
1answer
132 views
What's the use dirsync option for mount?
Today I stumbled upon this mount's option:
dirsync
All directory updates within the filesystem should be done synchronously.
This affects the following system calls: creat, link, unlink, ...
5
votes
3answers
335 views
tee + cat: use an output several times and then concatenate results
If I call some command, for instance an echo I can use the results from that command in several other commands with tee. Example:
echo "Hello world!" | tee >(command1) >(command2) ...
1
vote
1answer
82 views
Will files created under source directory after running `cp` be copied?
Suppose I use cp to copy a directory to another place. If the process takes long, and I create a new file under the source directory, will it be copied, or it depends? Thanks!
6
votes
4answers
2k views
using parallel to process unique input files to unique output files
I have a shell scripting problem where I'm given a directory full of input files (each file containing many input lines), and I need to process them individually, redirecting each of their outputs to ...
1
vote
0answers
554 views
“No PostgreSQL user name specified” - possible concurrency issues?
For my dissertation I'm running the same cronjob on around 300 machines, which is:
10,25,40,55 * * * * /path/to/db_script.sh 1>/dev/null
This script gets some values from the system (whether ...
1
vote
1answer
692 views
Capture user input while doing other things
Is there a way to have the output of a subprocess (something other than 'sleep' below) be dovetailed with the output from a foreground command-loop? For example:
while true
do
echo "updating ...
6
votes
3answers
1k views
How to launch a set of program inside tmux or gnome-terminal within a script?
I wanted to launch a few commands simultaneously in tmux or gnome-terminal or xfterminal ,
every different tab with a single command running , and close that tab when that command finishes.
Any ...
1
vote
1answer
2k views
How do you make a cross-process locking in Linux (C/C++)?
I need to make sure one process executes only in one instance at a time. On Windows you could use named mutex. But I have no idea what to use on Linux.
I think I've seen an approach were app creates ...
4
votes
2answers
513 views
rm -rf failing if deleting in parallel
rm -rf will fail if something tries to delete the same file tree (I think because rm enumerates the files first, then deletes).
A simple test:
# Terminal 1
for i in `seq 1 1000`; do mkdir -p ...
3
votes
2answers
557 views
Can there be multiple kernels executing at the same time?
I know that Linux OS's are typically multi-programmed, which means that multiple processes can be active at the same time. Can there be multiple kernels executing at the same time?
