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        !            23: .TH curl_easy_recv 3 "December 18, 2016" "libcurl 7.70.0" "libcurl Manual"
        !            24: 
        !            25: .SH NAME
        !            26: curl_easy_recv - receives raw data on an "easy" connection
        !            27: .SH SYNOPSIS
        !            28: .B #include <curl/easy.h>
        !            29: .sp
        !            30: .BI "CURLcode curl_easy_recv( CURL *" curl ", void *" buffer ","
        !            31: .BI "size_t " buflen ", size_t *" n ");"
        !            32: .ad
        !            33: .SH DESCRIPTION
        !            34: This function receives raw data from the established connection. You may use
        !            35: it together with \fIcurl_easy_send(3)\fP to implement custom protocols using
        !            36: libcurl. This functionality can be particularly useful if you use proxies
        !            37: and/or SSL encryption: libcurl will take care of proxy negotiation and
        !            38: connection set-up.
        !            39: 
        !            40: \fBbuffer\fP is a pointer to your buffer that will get the received
        !            41: data. \fBbuflen\fP is the maximum amount of data you can get in that
        !            42: buffer. The variable \fBn\fP points to will receive the number of received
        !            43: bytes.
        !            44: 
        !            45: To establish the connection, set \fICURLOPT_CONNECT_ONLY(3)\fP option before
        !            46: calling \fIcurl_easy_perform(3)\fP or \fIcurl_multi_perform(3)\fP. Note that
        !            47: \fIcurl_easy_recv(3)\fP does not work on connections that were created without
        !            48: this option.
        !            49: 
        !            50: The call will return \fBCURLE_AGAIN\fP if there is no data to read - the
        !            51: socket is used in non-blocking mode internally. When \fBCURLE_AGAIN\fP is
        !            52: returned, use your operating system facilities like \fIselect(2)\fP to wait
        !            53: for data. The socket may be obtained using \fIcurl_easy_getinfo(3)\fP with
        !            54: \fICURLINFO_ACTIVESOCKET(3)\fP.
        !            55: 
        !            56: Wait on the socket only if \fIcurl_easy_recv(3)\fP returns \fBCURLE_AGAIN\fP.
        !            57: The reason for this is libcurl or the SSL library may internally cache some
        !            58: data, therefore you should call \fIcurl_easy_recv(3)\fP until all data is
        !            59: read which would include any cached data.
        !            60: 
        !            61: Furthermore if you wait on the socket and it tells you there is data to read,
        !            62: \fIcurl_easy_recv(3)\fP may return \fBCURLE_AGAIN\fP if the only data that was
        !            63: read was for internal SSL processing, and no other data is available.
        !            64: 
        !            65: .SH AVAILABILITY
        !            66: Added in 7.18.2.
        !            67: .SH RETURN VALUE
        !            68: On success, returns \fBCURLE_OK\fP, stores the received data into
        !            69: \fBbuffer\fP, and the number of bytes it actually read into \fB*n\fP.
        !            70: 
        !            71: On failure, returns the appropriate error code.
        !            72: 
        !            73: The function may return \fBCURLE_AGAIN\fP. In this case, use your operating
        !            74: system facilities to wait until data can be read, and retry.
        !            75: 
        !            76: Reading exactly 0 bytes indicates a closed connection.
        !            77: 
        !            78: If there's no socket available to use from the previous transfer, this function
        !            79: returns \fBCURLE_UNSUPPORTED_PROTOCOL\fP.
        !            80: .SH EXAMPLE
        !            81: See \fBsendrecv.c\fP in \fBdocs/examples\fP directory for usage example.
        !            82: .SH "SEE ALSO"
        !            83: .BR curl_easy_setopt "(3), " curl_easy_perform "(3), "
        !            84: .BR curl_easy_getinfo "(3), "
        !            85: .BR curl_easy_send "(3) "