X11 Clipboard – Copy File to xclip and Paste to Firefox

Use the following tmux.conf with copy-pipe in the new versions of tmux (1.8+):

set -g mouse on
# To copy:
bind-key -n -t emacs-copy M-w copy-pipe "xclip -i -sel p -f | xclip -i -sel c "

# To paste:
bind-key -n C-y run "xclip -o | tmux load-buffer - ; tmux paste-buffer"

1. prefix+[ into copy-mode
2. select content with mouse(hold)
3. M-w to copy that part into system clipboard
4. C-y the paste it inside tmux, C-v to paste it inside other regular application like web browser.

With xclip:

while IFS= read -r line; do
  printf %s "$line" |
    xclip -l 1 -quiet -selection clipboard -in
done < file.txt

Replace %s with %s\n if you need the newline included.

With -l 1 xclip holds the CLIPBOARD selection for one request (by other applications doing Ctrl-V for instance), and then exits. You need -quiet for xclip to do that in foreground.

That won't work if you have an application like xclipboard running. Those applications try to always be the owner of the CLIPBOARD selection, so will steal it continuously from xclip.

If you have such an application running, you can either suspend or kill it, or you could use the PRIMARY selection instead (-selection primary, or omit -selection as primary is the default) and paste using the middle mouse button. Many terminal emulators can paste the PRIMARY selection upon Shift-Insert, some other upon Ctrl-Shift-Insert.

If you want to know who is stealing the CLIPBOARD selection from xclip, this may work:

xwininfo -id "$(xclip -selection clipboard -o -t CLIENT_WINDOW | od -vAn -tu8)" -wm

provided that application offers the CLIENT_WINDOW target (run xclip -selection clipboard -o -t TARGETS to see if it does).

See also expect (and dejagnu for a testing framework based on expect) and GNU screen to automate inserting text into terminal applications.