curl-config: 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/curl-config - from package: libcurl-devel

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

On Debian possible default full paths are:

/usr/bin/curl-config - from package: libcurl4-gnutls-dev
/usr/bin/curl-config - from package: libcurl4-nss-dev
/usr/bin/curl-config - from package: libcurl4-openssl-dev

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

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