Openssl 什么是；“文件存在”；误差平均值？

调用DTLSv1_listen（），返回0

然后使用SSL_get_error（）检索错误

SSL_error = SSL_ERROR_SYSCALL
errno = 17: "File exists"

这是什么意思？存在什么文件

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非常感谢您的帮助。

如果您能提供更多的上下文，那就太好了。但短时间的谷歌搜索导致了这段代码和评论： （第1085行）

1982          /*
1083          * Cert file exists, so load it.  Since OpenSSL doesn't provide the
1084          * equivalent of "SSL_use_certificate_chain_file", we actually have to
1085          * load the file twice.  The first call loads any extra certs after
1086          * the first one into chain-cert storage associated with the
1087          * SSL_context.  The second call loads the first cert (only) into the
1088          * SSL object, where it will be correctly paired with the private key
1089          * we load below.  We do it this way so that each connection
1090          * understands which subject cert to present, in case different
1091          * sslcert settings are used for different connections in the same
1092          * process.
1093          */