gview: 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/gview - from package: vim-X11

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

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