curl/docs/libcurl/opts/CURLINFO_LOCAL_IP.md
Daniel Stenberg eefcc1bda4
docs: introduce "curldown" for libcurl man page format
curldown is this new file format for libcurl man pages. It is markdown
inspired with differences:

- Each file has a set of leading headers with meta-data
- Supports a small subset of markdown
- Uses .md file extensions for editors/IDE/GitHub to treat them nicely
- Generates man pages very similar to the previous ones
- Generates man pages that still convert nicely to HTML on the website
- Detects and highlights mentions of curl symbols automatically (when
  their man page section is specified)

tools:

- cd2nroff: converts from curldown to nroff man page
- nroff2cd: convert an (old) nroff man page to curldown
- cdall: convert many nroff pages to curldown versions
- cd2cd: verifies and updates a curldown to latest curldown

This setup generates .3 versions of all the curldown versions at build time.

CI:

Since the documentation is now technically markdown in the eyes of many
things, the CI runs many more tests and checks on this documentation,
including proselint, link checkers and tests that make sure we capitalize the
first letter after a period...

Closes #12730
2024-01-23 00:29:02 +01:00

1.5 KiB

c SPDX-License-Identifier Title Section Source See-also
Copyright (C) Daniel Stenberg, <daniel.se>, et al. curl CURLINFO_LOCAL_IP 3 libcurl
CURLINFO_LOCAL_PORT (3)
CURLINFO_PRIMARY_IP (3)
curl_easy_getinfo (3)
curl_easy_setopt (3)

NAME

CURLINFO_LOCAL_IP - get local IP address of last connection

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_LOCAL_IP, char **ip);

DESCRIPTION

Pass a pointer to a char pointer to receive the pointer to a null-terminated string holding the IP address of the local end of most recent connection done with this curl handle. This string may be IPv6 when that is enabled. Note that you get a pointer to a memory area that is reused at next request so you need to copy the string if you want to keep the information.

The ip pointer is NULL or points to private memory. You MUST NOT free - it gets freed when you call curl_easy_cleanup(3) on the corresponding CURL handle.

PROTOCOLS

All

EXAMPLE

int main(void)
{
  char *ip;
  CURLcode res;
  CURL *curl = curl_easy_init();

  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

  /* Perform the transfer */
  res = curl_easy_perform(curl);
  /* Check for errors */
  if((res == CURLE_OK) &&
     !curl_easy_getinfo(curl, CURLINFO_LOCAL_IP, &ip) && ip) {
    printf("Local IP: %s\n", ip);
  }

  /* always cleanup */
  curl_easy_cleanup(curl);
}

AVAILABILITY

Added in 7.21.0

RETURN VALUE

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.