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Revision 1.240 by root, Sat Apr 25 14:12:48 2009 UTC vs.
Revision 1.241 by root, Sat Apr 25 14:23:26 2009 UTC

… …
3935way (note also that glib is the slowest event library known to man). 3935way (note also that glib is the slowest event library known to man).
3936 3936
3937There is no supported compilation method available on windows except 3937There is no supported compilation method available on windows except
3938embedding it into other applications. 3938embedding it into other applications.
3939 3939
3940Sensible signal handling is officially unsupported by Microsoft - libev
3941tries its best, but under most conditions, signals will simply not work.
3942
3940Not a libev limitation but worth mentioning: windows apparently doesn't 3943Not a libev limitation but worth mentioning: windows apparently doesn't
3941accept large writes: instead of resulting in a partial write, windows will 3944accept large writes: instead of resulting in a partial write, windows will
3942either accept everything or return C<ENOBUFS> if the buffer is too large, 3945either accept everything or return C<ENOBUFS> if the buffer is too large,
3943so make sure you only write small amounts into your sockets (less than a 3946so make sure you only write small amounts into your sockets (less than a
3944megabyte seems safe, but this apparently depends on the amount of memory 3947megabyte seems safe, but this apparently depends on the amount of memory
… …
3948the abysmal performance of winsockets, using a large number of sockets 3951the abysmal performance of winsockets, using a large number of sockets
3949is not recommended (and not reasonable). If your program needs to use 3952is not recommended (and not reasonable). If your program needs to use
3950more than a hundred or so sockets, then likely it needs to use a totally 3953more than a hundred or so sockets, then likely it needs to use a totally
3951different implementation for windows, as libev offers the POSIX readiness 3954different implementation for windows, as libev offers the POSIX readiness
3952notification model, which cannot be implemented efficiently on windows 3955notification model, which cannot be implemented efficiently on windows
3953(Microsoft monopoly games). 3956(due to Microsoft monopoly games).
3954 3957
3955A typical way to use libev under windows is to embed it (see the embedding 3958A typical way to use libev under windows is to embed it (see the embedding
3956section for details) and use the following F<evwrap.h> header file instead 3959section for details) and use the following F<evwrap.h> header file instead
3957of F<ev.h>: 3960of F<ev.h>:
3958 3961
… …
3994 3997
3995Early versions of winsocket's select only supported waiting for a maximum 3998Early versions of winsocket's select only supported waiting for a maximum
3996of C<64> handles (probably owning to the fact that all windows kernels 3999of C<64> handles (probably owning to the fact that all windows kernels
3997can only wait for C<64> things at the same time internally; Microsoft 4000can only wait for C<64> things at the same time internally; Microsoft
3998recommends spawning a chain of threads and wait for 63 handles and the 4001recommends spawning a chain of threads and wait for 63 handles and the
3999previous thread in each. Great). 4002previous thread in each. Sounds great!).
4000 4003
4001Newer versions support more handles, but you need to define C<FD_SETSIZE> 4004Newer versions support more handles, but you need to define C<FD_SETSIZE>
4002to some high number (e.g. C<2048>) before compiling the winsocket select 4005to some high number (e.g. C<2048>) before compiling the winsocket select
4003call (which might be in libev or elsewhere, for example, perl does its own 4006call (which might be in libev or elsewhere, for example, perl and many
4004select emulation on windows). 4007other interpreters do their own select emulation on windows).
4005 4008
4006Another limit is the number of file descriptors in the Microsoft runtime 4009Another limit is the number of file descriptors in the Microsoft runtime
4007libraries, which by default is C<64> (there must be a hidden I<64> fetish 4010libraries, which by default is C<64> (there must be a hidden I<64>
4008or something like this inside Microsoft). You can increase this by calling 4011fetish or something like this inside Microsoft). You can increase this
4009C<_setmaxstdio>, which can increase this limit to C<2048> (another 4012by calling C<_setmaxstdio>, which can increase this limit to C<2048>
4010arbitrary limit), but is broken in many versions of the Microsoft runtime 4013(another arbitrary limit), but is broken in many versions of the Microsoft
4011libraries.
4012
4013This might get you to about C<512> or C<2048> sockets (depending on 4014runtime libraries. This might get you to about C<512> or C<2048> sockets
4014windows version and/or the phase of the moon). To get more, you need to 4015(depending on windows version and/or the phase of the moon). To get more,
4015wrap all I/O functions and provide your own fd management, but the cost of 4016you need to wrap all I/O functions and provide your own fd management, but
4016calling select (O(n²)) will likely make this unworkable. 4017the cost of calling select (O(n²)) will likely make this unworkable.
4017 4018
4018=back 4019=back
4019 4020
4020=head2 PORTABILITY REQUIREMENTS 4021=head2 PORTABILITY REQUIREMENTS
4021 4022

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