pidcat: 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 Debian possible default full paths are:

/usr/bin/pidcat - from package: pidcat

You may install the required package with command apt-get install {package}

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