I have a problem when using curl on my linux script:



commande="curl -X POST -H \"Content-Type: application/json\" -H 
\"Cache-Control: no-cache\" -H
 \"Postman-Token: 111131da-8254-21b3-1b95-9c12954152c9\" 
-d '{\"auth\":{\"tenantName\":\"$tenantName\",\"passwordCredentials\":

When the output of the variable commande is copy pasted into the shell it works, but when i use :

res= $(eval $commande)

Neither one of those commands works, and this is the output error i usually get:

line 11: {"access":: command not found

PS: If i do

echo $commande

And then i copy past the result on the shell it works,If anyone can help me that would be great !

  • 1
    Check your spelling first, you have commande in one place, and comande in another. Also {"access": looks like part of a JSON snippet, but your first code snippet doesn't have that anywhere.
    – ilkkachu
    Mar 13, 2017 at 12:11
  • I made a mistake in writing the question but i've fixed it , and my Curl comman is working , the proof is that the output of the $commande variable when copy pasted works perfectly fine on my shell.
    – Kingofkech
    Mar 13, 2017 at 12:15
  • What response do you get from the res=`$commande` instruction? That attempt is less wrong than the other one.
    – roaima
    Mar 13, 2017 at 14:25
  • this is what i get: [ curl: (6) Could not resolve host: no-cache" curl: (6) Could not resolve host: 111131da-8254-21b3-1b95-9c12954152c9" curl: (1) Protocol ""http" not supported or disabled in libcurl] but it works in the console if i try it straight :/
    – Kingofkech
    Mar 13, 2017 at 14:28

1 Answer 1


A variable is for data, not code. Define a function. This also simplifies your quoting.



commande () {
    curl -X POST \
         -H "Content-Type: application/json" \
         -H "Cache-Control: no-cache" \
         -H "Postman-Token: ..." \
         -d@- \
         http://controller:5000/v2.0/tokens <<EOF
      "auth": {
        "tenantName": "$tenantName",
        "passwordCredentials": {
          "username": "$userName",
          "password": "$password"

The above also reads the JSON from a here-document (@- reads the argument for the -d option from standard input) instead of embedding it in a string to further simplify quoting.

However, it is also a bad idea to hand-code JSON like this if you aren't ensuring that the values of userName, passWord, and tennatnName are properly JSON-encoded. A better solution is to use something like jq to generate proper JSON for you.

commande () {
    auth: {
      tenantName: $tn,
      passwordCredentials: {
        username: $un,
        password: $pw
  jq -n --arg un "$userName" \
        --arg pw "$passWord" \
        --arg tn "$tenantName" "$json_template" |
    curl -X POST
         -H "Content-Type: application/json" \
         -H "Cache-Control: no-cache" \
         -H "Postman-Token: ..." \
         -d@- \
  • Does the function commande returns the output of the curl command as i wanted ?
    – Kingofkech
    Mar 13, 2017 at 14:11

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