xmlpatterns: 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/lib64/qt5/bin/xmlpatterns - from package: qt5-qtxmlpatterns-devel
/usr/lib/qt5/bin/xmlpatterns - from package: qt5-qtxmlpatterns-devel
/usr/bin/xmlpatterns - from package: qt-devel
/usr/lib64/qt4/bin/xmlpatterns - from package: qt-devel
/usr/lib/qt4/bin/xmlpatterns - from package: qt-devel

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

On Debian possible default full paths are:

/usr/bin/xmlpatterns - from package: qtchooser
/usr/lib/x86_64-linux-gnu/qt4/bin/xmlpatterns - from package: qt4-dev-tools
/usr/lib/x86_64-linux-gnu/qt5/bin/xmlpatterns - from package: qtxmlpatterns5-dev-tools

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

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