How do I bring a processes window to the foreground on X Windows? (C++)

Question

I have the PID for the process (and the name), I want to bring it to the front on linux (ubuntu). On mac I would simply do SetFrontProcess(pid), on windows I\'d

Answer 1

I thought this would be easy since /proc seemingly has the required data but /proc/${pid}/environ doesn't provide the correct window ID since it is usually the child of the parent who really owns the window where the process is running. To get the proper windowid you need to parse the xwininfo output then you can use xdotool to change the focus.

CMD_PID= && while IFS= read -r -d '' var; do 
if grep -q "^WINDOWID=" <<< "$var"; then 
 winid=$(printf '0x%x\n' $(sed 's/WINDOWID=//' <<< "${var}"))
 child_cnt=0 && IFS=$(echo -en "\n\b") && for a in $(xwininfo -root -tree | tac | sed -n "/${winid}/,\$p"); do 
 grep -q -i "children" <<< "${a}" && let child_cnt+=1
 ((${child_cnt} == 2)) && real_winid=$(grep -o '0x[^ ]*' <<< "${last_line}") && break
 last_line="${a}"
 done 
 xdotool windowraise ${real_winid} 
 break 
fi 
done < /proc/${CMD_PID}/environ