=pod =head1 NAME SSL_read - write bytes to a TLS/SSL connection. =head1 SYNOPSIS #include int SSL_write(SSL *ssl, char *buf, int num); =head1 DESCRIPTION SSL_write() writes B bytes from the buffer B into the specified B connection. =head1 NOTES If necessary, SSL_write() will negotiate a TLS/SSL session, if not already explicitly performed by SSL_connect() or SSL_accept(). If the peer requests a re-negotiation, it will be performed transparently during the SSL_write() operation. The behaviour of SSL_write() depends on the underlying BIO. If the underlying BIO is B, SSL_write() will only return, once the write operation has been finished or an error occurred. If the underlying BIO is B, SSL_write() will also return, when the underlying BIO could not satisfy the needs of SSL_write() to continue the operation. In this case a call to SSL_get_error() with the return value of SSL_write() will yield B or B. As at any time a re-negotiation is possible, a call to SSL_write() can also cause write operations! The calling process then must repeat the call after taking appropriate action to satisfy the needs of SSL_write(). The action depends on the underlying BIO. When using a non-blocking socket, nothing is to be done, but select() can be used to check for the required condition. When using a buffering BIO, like a BIO pair, data must be written into or retrieved out of the BIO before being able to continue. =head1 IMPORTANT When an SSL_write() operation has to be repeated because of B or B, it must be repeated with the same arguments. =head1 RETURN VALUES The following return values can occur: =over 4 =item E0 The write operation was successful, the return value is the number of bytes actually written to the TLS/SSL connection. =item 0 The write operation was not successful. Call SSL_get_error() with the return value B to find out, whether an error occurred. =item -1 The read operation was not successful, because either an error occurred or action must be taken by the calling process. Call SSL_get_error() with the return value B to find out the reason. =back =head1 SEE ALSO L, L, L, L =cut