flow-print: 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/bin/flow-print - from package: flow-tools

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

On Debian possible default full paths are:

/usr/bin/flow-print - from package: flow-tools

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