1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Title: curl_mime_encoder 5Section: 3 6Source: libcurl 7See-also: 8 - curl_mime_addpart (3) 9 - curl_mime_headers (3) 10 - curl_mime_subparts (3) 11Protocol: 12 - HTTP 13 - IMAP 14 - SMTP 15Added-in: 7.56.0 16--- 17 18# NAME 19 20curl_mime_encoder - set a mime part's encoder and content transfer encoding 21 22# SYNOPSIS 23 24~~~c 25#include <curl/curl.h> 26 27CURLcode curl_mime_encoder(curl_mimepart *part, const char *encoding); 28~~~ 29 30# DESCRIPTION 31 32curl_mime_encoder() requests a mime part's content to be encoded before being 33transmitted. 34 35*part* is the part's handle to assign an encoder. 36*encoding* is a pointer to a null-terminated encoding scheme. It may be 37set to NULL to disable an encoder previously attached to the part. The encoding 38scheme storage may safely be reused after this function returns. 39 40Setting a part's encoder multiple times is valid: only the value set by the 41last call is retained. 42 43Upon multipart rendering, the part's content is encoded according to the 44pertaining scheme and a corresponding *"Content-Transfer-Encoding"* header 45is added to the part. 46 47Supported encoding schemes are: 48 49"*binary*": the data is left unchanged, the header is added. 50 51"*8bit*": header added, no data change. 52 53"*7bit*": the data is unchanged, but is each byte is checked 54to be a 7-bit value; if not, a read error occurs. 55 56"*base64*": Data is converted to base64 encoding, then split in 57CRLF-terminated lines of at most 76 characters. 58 59"*quoted-printable*": data is encoded in quoted printable lines of 60at most 76 characters. Since the resulting size of the final data cannot be 61determined prior to reading the original data, it is left as unknown, causing 62chunked transfer in HTTP. For the same reason, this encoder may not be used 63with IMAP. This encoder targets text data that is mostly ASCII and should 64not be used with other types of data. 65 66If the original data is already encoded in such a scheme, a custom 67*Content-Transfer-Encoding* header should be added with 68curl_mime_headers(3) instead of setting a part encoder. 69 70Encoding should not be applied to multiparts, thus the use of this function on 71a part with content set with curl_mime_subparts(3) is strongly 72discouraged. 73 74# %PROTOCOLS% 75 76# EXAMPLE 77 78~~~c 79int main(void) 80{ 81 curl_mime *mime; 82 curl_mimepart *part; 83 84 CURL *curl = curl_easy_init(); 85 if(curl) { 86 /* create a mime handle */ 87 mime = curl_mime_init(curl); 88 89 /* add a part */ 90 part = curl_mime_addpart(mime); 91 92 /* send a file */ 93 curl_mime_filedata(part, "image.png"); 94 95 /* encode file data in base64 for transfer */ 96 curl_mime_encoder(part, "base64"); 97 } 98} 99~~~ 100 101# %AVAILABILITY% 102 103# RETURN VALUE 104 105CURLE_OK or a CURL error code upon failure. 106