Problem description
Command output is not always displayed when the command is also making the terminal exiting.
Only "[Process completed (code X) - press Enter]" is displayed.

Steps to reproduce
Make a small C program like:

#include <unistd.h>
int main(void)
{
    write(1, "########\n", 9);
    return 123;
}

Execute it with "exec ./smallprog" in a terminal.

Expected behavior
"########" should be always displayed.

Additional information
Some race condition occur, most of the time the output is displayed.
Sounds like sometime the process exit is processed before all buffered output is processed.
Also occur with shell script output.
Happen on stdout or stderr.
The bug is more apparent with Termux:Widget since the terminal is closed after execution, sometime on command error nothing is displayed.