CURLOPT_BUFFERSIZE.3 2.6 KB

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  23. .TH CURLOPT_BUFFERSIZE 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
  24. .SH NAME
  25. CURLOPT_BUFFERSIZE \- receive buffer size
  26. .SH SYNOPSIS
  27. .nf
  28. #include <curl/curl.h>
  29. CURLcode curl_easy_setopt(CURL *handle, CURLOPT_BUFFERSIZE, long size);
  30. .fi
  31. .SH DESCRIPTION
  32. Pass a long specifying your preferred \fIsize\fP (in bytes) for the receive
  33. buffer in libcurl. The main point of this would be that the write callback
  34. gets called more often and with smaller chunks. Secondly, for some protocols,
  35. there's a benefit of having a larger buffer for performance.
  36. This is just treated as a request, not an order. You cannot be guaranteed to
  37. actually get the given size.
  38. This buffer size is by default \fICURL_MAX_WRITE_SIZE\fP (16kB). The maximum
  39. buffer size allowed to be set is \fICURL_MAX_READ_SIZE\fP (512kB). The minimum
  40. buffer size allowed to be set is 1024.
  41. DO NOT set this option on a handle that is currently used for an active
  42. transfer as that may lead to unintended consequences.
  43. .SH DEFAULT
  44. CURL_MAX_WRITE_SIZE (16kB)
  45. .SH PROTOCOLS
  46. All
  47. .SH EXAMPLE
  48. .nf
  49. CURL *curl = curl_easy_init();
  50. if(curl) {
  51. curl_easy_setopt(curl, CURLOPT_URL, "sftp://example.com/foo.bin");
  52. /* ask libcurl to allocate a larger receive buffer */
  53. curl_easy_setopt(curl, CURLOPT_BUFFERSIZE, 120000L);
  54. ret = curl_easy_perform(curl);
  55. curl_easy_cleanup(curl);
  56. }
  57. .fi
  58. .SH AVAILABILITY
  59. Added in 7.10. Growing the buffer was added in 7.53.0.
  60. .SH RETURN VALUE
  61. Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
  62. .SH "SEE ALSO"
  63. .BR CURLOPT_MAX_RECV_SPEED_LARGE "(3), " CURLOPT_WRITEFUNCTION "(3), "