xdvi: 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/xdvi - from package: xdvik

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

On Debian possible default full paths are:

/usr/bin/xdvi - from package: texlive-binaries

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

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