docs/libcurl/curl_slist_append.3

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.TH curl_slist_append 3 "November 05, 2020" "libcurl 7.78.0" "libcurl Manual"

.SH NAME
curl_slist_append - add a string to an slist
.SH SYNOPSIS
.B #include <curl/curl.h>
.sp
.BI "struct curl_slist *curl_slist_append(struct curl_slist *" list,
.BI "const char * "string ");"
.ad
.SH DESCRIPTION
\fIcurl_slist_append(3)\fP appends a string to a linked list of strings. The
existing \fBlist\fP should be passed as the first argument and the new list is
returned from this function. Pass in NULL in the \fBlist\fP argument to create
a new list. The specified \fBstring\fP has been appended when this function
returns. \fIcurl_slist_append(3)\fP copies the string.

The list should be freed again (after usage) with
\fIcurl_slist_free_all(3)\fP.
.SH RETURN VALUE
A null pointer is returned if anything went wrong, otherwise the new list
pointer is returned. To avoid overwriting an existing non-empty list on
failure, the new list should be returned to a temporary variable which can
be tested for NULL before updating the original list pointer.
.SH EXAMPLE
.nf
CURL *handle;
struct curl_slist *slist=NULL;
struct curl_slist *temp=NULL;

slist = curl_slist_append(slist, "pragma:");

if (slist == NULL)
  return -1;

temp = curl_slist_append(slist, "Accept:")

if (temp == NULL) {
  curl_slist_free_all(slist);
  return -1;
}

slist = temp;

curl_easy_setopt(handle, CURLOPT_HTTPHEADER, slist);

curl_easy_perform(handle);

curl_slist_free_all(slist); /* free the list again */
.fi
.SH "SEE ALSO"
.BR curl_slist_free_all "(3), "