… | |
… | |
2108 | |
2108 | |
2109 | When the first watcher gets started will libev actually register something |
2109 | When the first watcher gets started will libev actually register something |
2110 | with the kernel (thus it coexists with your own signal handlers as long as |
2110 | with the kernel (thus it coexists with your own signal handlers as long as |
2111 | you don't register any with libev for the same signal). |
2111 | you don't register any with libev for the same signal). |
2112 | |
2112 | |
2113 | Both the signal mask state (C<sigprocmask>) and the signal handler state |
|
|
2114 | (C<sigaction>) are unspecified after starting a signal watcher (and after |
|
|
2115 | sotpping it again), that is, libev might or might not block the signal, |
|
|
2116 | and might or might not set or restore the installed signal handler. |
|
|
2117 | |
|
|
2118 | If possible and supported, libev will install its handlers with |
2113 | If possible and supported, libev will install its handlers with |
2119 | C<SA_RESTART> (or equivalent) behaviour enabled, so system calls should |
2114 | C<SA_RESTART> (or equivalent) behaviour enabled, so system calls should |
2120 | not be unduly interrupted. If you have a problem with system calls getting |
2115 | not be unduly interrupted. If you have a problem with system calls getting |
2121 | interrupted by signals you can block all signals in an C<ev_check> watcher |
2116 | interrupted by signals you can block all signals in an C<ev_check> watcher |
2122 | and unblock them in an C<ev_prepare> watcher. |
2117 | and unblock them in an C<ev_prepare> watcher. |
|
|
2118 | |
|
|
2119 | =head3 The special problem of inheritance over execve |
|
|
2120 | |
|
|
2121 | Both the signal mask (C<sigprocmask>) and the signal disposition |
|
|
2122 | (C<sigaction>) are unspecified after starting a signal watcher (and after |
|
|
2123 | stopping it again), that is, libev might or might not block the signal, |
|
|
2124 | and might or might not set or restore the installed signal handler. |
|
|
2125 | |
|
|
2126 | While this does not matter for the signal disposition (libev never |
|
|
2127 | sets signals to C<SIG_IGN>, so handlers will be reset to C<SIG_DFL> on |
|
|
2128 | C<execve>), this matters for the signal mask: many programs do not expect |
|
|
2129 | many signals to be blocked. |
|
|
2130 | |
|
|
2131 | This means that before calling C<exec> (from the child) you should reset |
|
|
2132 | the signal mask to whatever "default" you expect (all clear is a good |
|
|
2133 | choice usually). |
2123 | |
2134 | |
2124 | =head3 Watcher-Specific Functions and Data Members |
2135 | =head3 Watcher-Specific Functions and Data Members |
2125 | |
2136 | |
2126 | =over 4 |
2137 | =over 4 |
2127 | |
2138 | |
… | |
… | |
3663 | be used is the winsock select). This means that it will call |
3674 | be used is the winsock select). This means that it will call |
3664 | C<_get_osfhandle> on the fd to convert it to an OS handle. Otherwise, |
3675 | C<_get_osfhandle> on the fd to convert it to an OS handle. Otherwise, |
3665 | it is assumed that all these functions actually work on fds, even |
3676 | it is assumed that all these functions actually work on fds, even |
3666 | on win32. Should not be defined on non-win32 platforms. |
3677 | on win32. Should not be defined on non-win32 platforms. |
3667 | |
3678 | |
3668 | =item EV_FD_TO_WIN32_HANDLE |
3679 | =item EV_FD_TO_WIN32_HANDLE(fd) |
3669 | |
3680 | |
3670 | If C<EV_SELECT_IS_WINSOCKET> is enabled, then libev needs a way to map |
3681 | If C<EV_SELECT_IS_WINSOCKET> is enabled, then libev needs a way to map |
3671 | file descriptors to socket handles. When not defining this symbol (the |
3682 | file descriptors to socket handles. When not defining this symbol (the |
3672 | default), then libev will call C<_get_osfhandle>, which is usually |
3683 | default), then libev will call C<_get_osfhandle>, which is usually |
3673 | correct. In some cases, programs use their own file descriptor management, |
3684 | correct. In some cases, programs use their own file descriptor management, |
3674 | in which case they can provide this function to map fds to socket handles. |
3685 | in which case they can provide this function to map fds to socket handles. |
|
|
3686 | |
|
|
3687 | =item EV_WIN32_HANDLE_TO_FD(handle) |
|
|
3688 | |
|
|
3689 | If C<EV_SELECT_IS_WINSOCKET> then libev maps handles to file descriptors |
|
|
3690 | using the standard C<_open_osfhandle> function. For programs implementing |
|
|
3691 | their own fd to handle mapping, overwriting this function makes it easier |
|
|
3692 | to do so. This can be done by defining this macro to an appropriate value. |
|
|
3693 | |
|
|
3694 | =item EV_WIN32_CLOSE_FD(fd) |
|
|
3695 | |
|
|
3696 | If programs implement their own fd to handle mapping on win32, then this |
|
|
3697 | macro can be used to override the C<close> function, useful to unregister |
|
|
3698 | file descriptors again. Note that the replacement function has to close |
|
|
3699 | the underlying OS handle. |
3675 | |
3700 | |
3676 | =item EV_USE_POLL |
3701 | =item EV_USE_POLL |
3677 | |
3702 | |
3678 | If defined to be C<1>, libev will compile in support for the C<poll>(2) |
3703 | If defined to be C<1>, libev will compile in support for the C<poll>(2) |
3679 | backend. Otherwise it will be enabled on non-win32 platforms. It |
3704 | backend. Otherwise it will be enabled on non-win32 platforms. It |