Code:
; Create and hide the window
window -hsle @info
; Use a loop below if necessary, to put data into window.
aline @info WHATEVER

; Here you have two choices,
; Make the window active and put it back into switchbar/treeview.
; Or instead of making it active you could just close it.

; Uncommenting the line below will make the window active.
; window -aw3 @info
; Uncommenting the line below will close the window.
; window -c @info


This makes the @info window a "sorted list box" and since it's "hidden" to start off with, it allows your text to be written to the window a bit faster, AND prevents it from stealing focus. Especially if you choose to close the window after you're finished instead of making it the active window.

If you still prefer to actually *write* to a file, you can use:

fopen myfile the_file_here.txt
fwrite -n myfile %data
fwrite -n myfile %data2
fwrite -n myfile %data3
fclose myfile

The above works much faster then the standard /write.