Can I call curl_slist_free_all right after I set CURLOPT

Can I call curl_slist_free_all right after I set CURLOPT_HTTPHEADER?

up vote
3
down vote

favorite

Can I do this?

curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);

curl_slist_free_all(headerlist);

That is, can I free the header list before I send the request? Does curl make a copy?

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

1

Just a note for the future: If you run into a 3rd party binary library and you can't look and see, what you can do is set the option, then overwrite your value with something obvious and then call the operation. If the original value shows up you know it made a copy. If the new value shows up, you know it didn't.
– Zan Lynx
Oct 2 '14 at 23:21

1

This is now also clarified in the CURLOPT_HTTPHEADER man page for future hackers.
– Daniel Stenberg
Oct 3 '14 at 11:37

add a comment |

up vote
3
down vote

favorite

Can I do this?

curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);

curl_slist_free_all(headerlist);

That is, can I free the header list before I send the request? Does curl make a copy?

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

1

Just a note for the future: If you run into a 3rd party binary library and you can't look and see, what you can do is set the option, then overwrite your value with something obvious and then call the operation. If the original value shows up you know it made a copy. If the new value shows up, you know it didn't.
– Zan Lynx
Oct 2 '14 at 23:21

1

This is now also clarified in the CURLOPT_HTTPHEADER man page for future hackers.
– Daniel Stenberg
Oct 3 '14 at 11:37

add a comment |

up vote
3
down vote

favorite

Can I do this?

curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);

curl_slist_free_all(headerlist);

That is, can I free the header list before I send the request? Does curl make a copy?

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

Can I do this?

curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);

curl_slist_free_all(headerlist);

That is, can I free the header list before I send the request? Does curl make a copy?

c libcurl

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

asked Oct 2 '14 at 22:18

bugloaf

1,49711935

1

Just a note for the future: If you run into a 3rd party binary library and you can't look and see, what you can do is set the option, then overwrite your value with something obvious and then call the operation. If the original value shows up you know it made a copy. If the new value shows up, you know it didn't.
– Zan Lynx
Oct 2 '14 at 23:21

1

This is now also clarified in the CURLOPT_HTTPHEADER man page for future hackers.
– Daniel Stenberg
Oct 3 '14 at 11:37

add a comment |

1

Just a note for the future: If you run into a 3rd party binary library and you can't look and see, what you can do is set the option, then overwrite your value with something obvious and then call the operation. If the original value shows up you know it made a copy. If the new value shows up, you know it didn't.
– Zan Lynx
Oct 2 '14 at 23:21

1

This is now also clarified in the CURLOPT_HTTPHEADER man page for future hackers.
– Daniel Stenberg
Oct 3 '14 at 11:37

Just a note for the future: If you run into a 3rd party binary library and you can't look and see, what you can do is set the option, then overwrite your value with something obvious and then call the operation. If the original value shows up you know it made a copy. If the new value shows up, you know it didn't.
– Zan Lynx
Oct 2 '14 at 23:21

This is now also clarified in the CURLOPT_HTTPHEADER man page for future hackers.
– Daniel Stenberg
Oct 3 '14 at 11:37

add a comment |

2 Answers
2

active

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up vote
6
down vote

accepted

No. In the source the setopt function just saves your pointer.

case CURLOPT_HTTPHEADER:

    /*

     * Set a list with HTTP headers to use (or replace internals with)

     */

    data->set.headers = va_arg(param, struct curl_slist *);

    break;

answered Oct 2 '14 at 23:14

mukunda

1,998815

add a comment |

up vote
0
down vote

And additionally the list should live during the lifetime of the program, or at least until everything is done with the curl_perform.

answered Nov 11 at 18:08

UtkuBulkan

552

add a comment |

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2 Answers
2

active

oldest

votes

2 Answers
2

active

oldest

votes

up vote
6
down vote

accepted

No. In the source the setopt function just saves your pointer.

case CURLOPT_HTTPHEADER:

    /*

     * Set a list with HTTP headers to use (or replace internals with)

     */

    data->set.headers = va_arg(param, struct curl_slist *);

    break;

answered Oct 2 '14 at 23:14

mukunda

1,998815

add a comment |

up vote
6
down vote

accepted

No. In the source the setopt function just saves your pointer.

case CURLOPT_HTTPHEADER:

    /*

     * Set a list with HTTP headers to use (or replace internals with)

     */

    data->set.headers = va_arg(param, struct curl_slist *);

    break;

answered Oct 2 '14 at 23:14

mukunda

1,998815

add a comment |

up vote
6
down vote

accepted

No. In the source the setopt function just saves your pointer.

case CURLOPT_HTTPHEADER:

    /*

     * Set a list with HTTP headers to use (or replace internals with)

     */

    data->set.headers = va_arg(param, struct curl_slist *);

    break;

answered Oct 2 '14 at 23:14

mukunda

1,998815

No. In the source the setopt function just saves your pointer.

case CURLOPT_HTTPHEADER:

    /*

     * Set a list with HTTP headers to use (or replace internals with)

     */

    data->set.headers = va_arg(param, struct curl_slist *);

    break;

answered Oct 2 '14 at 23:14

mukunda

1,998815

answered Oct 2 '14 at 23:14

mukunda

1,998815

answered Oct 2 '14 at 23:14

mukunda

1,998815

answered Oct 2 '14 at 23:14

mukunda

1,998815

add a comment |

up vote
0
down vote

And additionally the list should live during the lifetime of the program, or at least until everything is done with the curl_perform.

answered Nov 11 at 18:08

UtkuBulkan

552

add a comment |

up vote
0
down vote

And additionally the list should live during the lifetime of the program, or at least until everything is done with the curl_perform.

answered Nov 11 at 18:08

UtkuBulkan

552

add a comment |

up vote
0
down vote

And additionally the list should live during the lifetime of the program, or at least until everything is done with the curl_perform.

answered Nov 11 at 18:08

UtkuBulkan

552

And additionally the list should live during the lifetime of the program, or at least until everything is done with the curl_perform.

answered Nov 11 at 18:08

UtkuBulkan

552

answered Nov 11 at 18:08

UtkuBulkan

552

answered Nov 11 at 18:08

UtkuBulkan

552

answered Nov 11 at 18:08

UtkuBulkan

552

add a comment |

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