merge r3294, r3305: Fix a bug introduced in r2032: After a child process has read a terminate message from a channel, the process tries to read the channel again. The kernel (at least FreeBSD) may preempt the process and sends a SIGIO signal to a master process. The master process sends a new terminate message, the kernel switches again to the the child process, and the child process reads the messages instead of an EAGAIN error. And this may repeat over and over. Being that the child process can not exit the cycle and test the termination flag set by the message handler. The fix disallow the master process to send a new terminate message on SIGIO signal reception. It may send the message only on SIGALARM signal.

/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_LINUX_H_INCLUDED_
#define _NGX_LINUX_H_INCLUDED_


ngx_chain_t *ngx_linux_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);

extern int ngx_linux_rtsig_max;


#endif /* _NGX_LINUX_H_INCLUDED_ */