qemu/chardev/char-mux.c
/**
 * Called after processing of default and command-line-specified
 * chardevs to deliver CHR_EVENT_OPENED events to any FEs attached
 * to a mux chardev. This is done here to ensure that
 * output/prompts/banners are only displayed for the FE that has
 * focus when initial command-line processing/machine init is
 * completed.
 *
 * After this point, any new FE attached to any new or existing
 * mux will receive CHR_EVENT_OPENED notifications for the BE
 * immediately.
 */
Called after processing of default and command-line-specified
chardevs to deliver CHR_EVENT_OPENED events to any FEs attached
to a mux chardev. This is done here to ensure that
output/prompts/banners are only displayed for the FE that has
focus when initial command-line processing/machine init is
completed.

After this point, any new FE attached to any new or existing
mux will receive CHR_EVENT_OPENED notifications for the BE
immediately.
Called after processing of default and command - line - specified chardevs to deliver CHR_EVENT_OPENED events to any FEs attached to a mux chardev . This is done here to ensure that output / prompts / banners are only displayed for the FE that has focus when initial command - line processing / machine init is completed . After this point any new FE attached to any new or existing mux will receive CHR_EVENT_OPENED notifications for the BE immediately .
static int open_muxes(Chardev *chr)
{
    mux_chr_send_all_event(chr, CHR_EVENT_OPENED);
    qemu_chr_be_event(chr, CHR_EVENT_OPENED);
    return 0;
}
static int open_muxes ( Chardev * chr ) { mux_chr_send_all_event ( chr , CHR_EVENT_OPENED ) ; qemu_chr_be_event ( chr , CHR_EVENT_OPENED ) ; return 0 ; }
Called after processing of default and command-line-specified
 chardevs to deliver CHR_EVENT_OPENED events to any FEs attached
 to a mux chardev.
Called after processing of default and command - line - specified chardevs to deliver CHR_EVENT_OPENED events to any FEs attached to a mux chardev .
/* send OPENED to all already-attached FEs */ /*
     * mark mux as OPENED so any new FEs will immediately receive
     * OPENED event
     */