2
votes
2answers
182 views

Any way in Bash to write to a file every X seconds without closing it?

The hardware watchdog on my system needs a 0 written to /dev/watchdog at less than 60 seconds interval or it will fire. The file handle must be kept open however or the watchdog is then disabled. ...
3
votes
1answer
609 views

Parameretrize file descriptor number to open a tcp socket in shell script

I'm tried to parameretrize in a variable the file descriptor number to open a tcp socket using exec command but it failed. Only work correctly when file descriptor number is a constant. In the next ...
9
votes
1answer
7k views

File descriptors & shell scripting

I am having a very hard time understanding how does one use file descriptors in shell scripts. I know the basics such as exec 5 > /tmp/foo So fd 5 is attached to foo for writing. exec 6 < ...