bltk_winid: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/lib64/bltk/bin/bltk_winid - from package: bltk

You may install the required package with command yum install {package}
Error in other languages:
bltk_winid: bevel nie gevind nie
bltk_winid: comandă negăsită
bltk_winid: comando não encontrado
bltk_winid: commande introuvable
bltk_winid: command not found
bltk_winid: käsku ei ole
bltk_winid: không tìm thấy lệnh
bltk_winid: komanda nerasta
bltk_winid: Kommando nicht gefunden.
bltk_winid: kommandot finns inte
bltk_winid: komut yok
bltk_winid: nie znaleziono polecenia
bltk_winid: níor aimsíodh an t-ordú
bltk_winid: no se encontró la orden
bltk_winid: no s'ha trobat l'ordre
bltk_winid: opdracht niet gevonden
bltk_winid: parancs nem található
bltk_winid: perintah tidak ditemukan
bltk_winid: príkaz nenájdený
bltk_winid: příkaz nenalezen
bltk_winid: команда не найдена
bltk_winid: командата не е открита
bltk_winid: 命令找不到
bltk_winid: コマンドが見つかりません