NGX_POP3_NOOP 70 mail/ngx_mail_parse.c s->command = NGX_POP3_NOOP; NGX_POP3_NOOP 180 mail/ngx_mail_pop3_handler.c case NGX_POP3_NOOP: NGX_POP3_NOOP 210 mail/ngx_mail_pop3_handler.c case NGX_POP3_NOOP: