memcat: 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/memcat - from package: libmemcached10
/usr/bin/memcat - from package: libmemcached

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

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