showfoto: 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/showfoto - from package: digikam

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

On Debian possible default full paths are:

/usr/bin/showfoto - from package: showfoto

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

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