dbjdbj/dbjsyslog repository overview

New to containers? This video might help⁠.

⁠The Requirement

Imagine somelegacyapp is 20+ years old binary, but now your salary provider wants its output to go to the container log.

⁠The Solution

You put the said binary in the image, using e.g alpine:latest in your Dockerfile, build it and then start the container, for example like this

docker run -itd --name mycontainername  imagename

Then you go to the just started container shell and this is how you do it:

# linux redirection jamboree
#  redirect both STDOUT and STDERR to the container log
./somelegacyapp &>/dev/console 
#  redirect only the STDOUT to the container log
./somelegacyapp 1>/dev/console 
#  redirect only the STDERR to the container log
./somelegacyapp 2>/dev/console 

And then emboldened and invigorated you might try to write streams 1 (STDOUT) and 2 (STDERR) to log.txt and then redirect the log.txt to the container log, and then run the whole as a daemon!

./somelegacyapp &>log.txt>/dev/console &

Note: it is important not to insert spaces above!

Generally, peek around a few simple sources in the /dbj folder of this Alpine build.