swarp: 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/swarp - from package: swarp

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

On Debian possible default full paths are:

/usr/bin/swarp - from package: suckless-tools
/usr/bin/swarp - from package: swarp

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

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