pbs_tclsh: 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/pbs_tclsh - from package: torque-client

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

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