gshhgtograss: 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/gshhgtograss - from package: GMT

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

On Debian possible default full paths are:

/usr/lib/gmt/bin/gshhgtograss - from package: GMT

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

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