Re:Bash process substitution
by jonaf on Sunday February 08, 2015 @07:53PM
(#9019253)
One neat trick I've found is using `exec` in conjunction with process substitution to effect and gather changes to the current environment within the context of a script (usually not as useful with a pty attached).
Example: how can you redirect stdout to syslog, a specified log file, and stdout? Easy, with tee, right?
```
$my_command | tee -a >(logger -t "$0[my_command]" -p "local0.INFO") "/var/log/my_logs/$(date +%s).log")
```
Okay, that's cool. But, I have to run it for every command in my script! How inconvenient. Is there a way we can make all stdout for the script do this?
Yes! Use `exec`!
```
exec &> tee -a >(logger -t "$0[my_command]" -p "local0.INFO") "/var/log/my_logs/$(date +%s).log")
Example: how can you redirect stdout to syslog, a specified log file, and stdout? Easy, with tee, right?
``` $my_command | tee -a >(logger -t "$0[my_command]" -p "local0.INFO") "/var/log/my_logs/$(date +%s).log") ```
Okay, that's cool. But, I have to run it for every command in my script! How inconvenient. Is there a way we can make all stdout for the script do this?
Yes! Use `exec`!
``` exec &> tee -a >(logger -t "$0[my_command]" -p "local0.INFO") "/var/log/my_logs/$(date +%s).log")
$my_command ```