gpiv_hdf2piv: 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/gpiv_hdf2piv - from package: gpivtools-mpi
/usr/bin/gpiv_hdf2piv - from package: gpivtools

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

Error in other languages:
gpiv_hdf2piv: bevel nie gevind nie
gpiv_hdf2piv: comandă negăsită
gpiv_hdf2piv: comando não encontrado
gpiv_hdf2piv: commande introuvable
gpiv_hdf2piv: command not found
gpiv_hdf2piv: käsku ei ole
gpiv_hdf2piv: không tìm thấy lệnh
gpiv_hdf2piv: komanda nerasta
gpiv_hdf2piv: Kommando nicht gefunden.
gpiv_hdf2piv: kommandot finns inte
gpiv_hdf2piv: komut yok
gpiv_hdf2piv: nie znaleziono polecenia
gpiv_hdf2piv: níor aimsíodh an t-ordú
gpiv_hdf2piv: no se encontró la orden
gpiv_hdf2piv: no s'ha trobat l'ordre
gpiv_hdf2piv: opdracht niet gevonden
gpiv_hdf2piv: parancs nem található
gpiv_hdf2piv: perintah tidak ditemukan
gpiv_hdf2piv: príkaz nenájdený
gpiv_hdf2piv: příkaz nenalezen
gpiv_hdf2piv: команда не найдена
gpiv_hdf2piv: командата не е открита
gpiv_hdf2piv: 命令找不到
gpiv_hdf2piv: コマンドが見つかりません