mirror of https://github.com/curl/curl.git synced 2024-12-09 06:30:06 +08:00

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

2.5 KiB

Raw Blame History

SPDX-License-Identifier

Title

Section

Source

See-also

curl

CURLOPT_ERRORBUFFER

libcurl

CURLOPT_DEBUGFUNCTION (3)

CURLOPT_VERBOSE (3)

curl_easy_strerror (3)

curl_multi_strerror (3)

curl_share_strerror (3)

curl_url_strerror (3)

NAME

CURLOPT_ERRORBUFFER - error buffer for error messages

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_ERRORBUFFER, char *buf);

DESCRIPTION

Pass a char pointer to a buffer that libcurl may use to store human readable error messages on failures or problems. This may be more helpful than just the return code from curl_easy_perform(3) and related functions. The buffer must be at least CURL_ERROR_SIZE bytes big.

You must keep the associated buffer available until libcurl no longer needs it. Failing to do so might cause odd behavior or even crashes. libcurl might need it until you call curl_easy_cleanup(3) or you set the same option again to use a different pointer.

Do not rely on the contents of the buffer unless an error code was returned. Since 7.60.0 libcurl initializes the contents of the error buffer to an empty string before performing the transfer. For earlier versions if an error code was returned but there was no error detail then the buffer was untouched.

Consider CURLOPT_VERBOSE(3) and CURLOPT_DEBUGFUNCTION(3) to better debug and trace why errors happen.

DEFAULT

NULL

PROTOCOLS

All

EXAMPLE

#include <string.h> /* for strlen() */
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    char errbuf[CURL_ERROR_SIZE];

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

    /* provide a buffer to store errors in */
    curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errbuf);

    /* set the error buffer as empty before performing a request */
    errbuf[0] = 0;

    /* perform the request */
    res = curl_easy_perform(curl);

    /* if the request did not complete correctly, show the error
    information. if no detailed error information was written to errbuf
    show the more generic information from curl_easy_strerror instead.
    */
    if(res != CURLE_OK) {
      size_t len = strlen(errbuf);
      fprintf(stderr, "\nlibcurl: (%d) ", res);
      if(len)
        fprintf(stderr, "%s%s", errbuf,
                ((errbuf[len - 1] != '\n') ? "\n" : ""));
      else
        fprintf(stderr, "%s\n", curl_easy_strerror(res));
    }
  }
}

AVAILABILITY

Always

RETURN VALUE

Returns CURLE_OK

2.5 KiB Raw Blame History