czmq_selftest: command not found

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/bin/czmq_selftest - from package: czmq-devel

You may install the required package with command yum install {package}

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