bltk_get_realpath: 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_get_realpath - from package: bltk

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