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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.273 by root, Fri Jun 23 22:33:06 2017 UTC vs.
Revision 1.277 by root, Fri Sep 22 12:17:49 2017 UTC

… …
277 IO::AIO::idle_timeout $seconds 277 IO::AIO::idle_timeout $seconds
278 IO::AIO::max_outstanding $maxreqs 278 IO::AIO::max_outstanding $maxreqs
279 IO::AIO::nreqs 279 IO::AIO::nreqs
280 IO::AIO::nready 280 IO::AIO::nready
281 IO::AIO::npending 281 IO::AIO::npending
282 IO::AIO::min_fdlimit $nfd;
282 283
283 IO::AIO::sendfile $ofh, $ifh, $offset, $count 284 IO::AIO::sendfile $ofh, $ifh, $offset, $count
284 IO::AIO::fadvise $fh, $offset, $len, $advice 285 IO::AIO::fadvise $fh, $offset, $len, $advice
285 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] 286 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
286 IO::AIO::munmap $scalar 287 IO::AIO::munmap $scalar
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958 959
959Try to copy the I<file> (directories not supported as either source or 960Try to copy the I<file> (directories not supported as either source or
960destination) from C<$srcpath> to C<$dstpath> and call the callback with 961destination) from C<$srcpath> to C<$dstpath> and call the callback with
961a status of C<0> (ok) or C<-1> (error, see C<$!>). 962a status of C<0> (ok) or C<-1> (error, see C<$!>).
962 963
964Existing destination files will be truncated.
965
963This is a composite request that creates the destination file with 966This is a composite request that creates the destination file with
964mode 0200 and copies the contents of the source file into it using 967mode 0200 and copies the contents of the source file into it using
965C<aio_sendfile>, followed by restoring atime, mtime, access mode and 968C<aio_sendfile>, followed by restoring atime, mtime, access mode and
966uid/gid, in that order. 969uid/gid, in that order.
967 970
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1076Scans a directory (similar to C<aio_readdir>) but additionally tries to 1079Scans a directory (similar to C<aio_readdir>) but additionally tries to
1077efficiently separate the entries of directory C<$path> into two sets of 1080efficiently separate the entries of directory C<$path> into two sets of
1078names, directories you can recurse into (directories), and ones you cannot 1081names, directories you can recurse into (directories), and ones you cannot
1079recurse into (everything else, including symlinks to directories). 1082recurse into (everything else, including symlinks to directories).
1080 1083
1081C<aio_scandir> is a composite request that creates of many sub requests_ 1084C<aio_scandir> is a composite request that generates many sub requests.
1082C<$maxreq> specifies the maximum number of outstanding aio requests that 1085C<$maxreq> specifies the maximum number of outstanding aio requests that
1083this function generates. If it is C<< <= 0 >>, then a suitable default 1086this function generates. If it is C<< <= 0 >>, then a suitable default
1084will be chosen (currently 4). 1087will be chosen (currently 4).
1085 1088
1086On error, the callback is called without arguments, otherwise it receives 1089On error, the callback is called without arguments, otherwise it receives
… …
1605There are some caveats: when directories get renamed (or deleted), the 1608There are some caveats: when directories get renamed (or deleted), the
1606pathname string doesn't change, so will point to the new directory (or 1609pathname string doesn't change, so will point to the new directory (or
1607nowhere at all), while the directory fd, if available on the system, 1610nowhere at all), while the directory fd, if available on the system,
1608will still point to the original directory. Most functions accepting a 1611will still point to the original directory. Most functions accepting a
1609pathname will use the directory fd on newer systems, and the string on 1612pathname will use the directory fd on newer systems, and the string on
1610older systems. Some functions (such as realpath) will always rely on the 1613older systems. Some functions (such as C<aio_realpath>) will always rely on
1611string form of the pathname. 1614the string form of the pathname.
1612 1615
1613So this functionality is mainly useful to get some protection against 1616So this functionality is mainly useful to get some protection against
1614C<chdir>, to easily get an absolute path out of a relative path for future 1617C<chdir>, to easily get an absolute path out of a relative path for future
1615reference, and to speed up doing many operations in the same directory 1618reference, and to speed up doing many operations in the same directory
1616(e.g. when stat'ing all files in a directory). 1619(e.g. when stat'ing all files in a directory).
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2008This is a very bad function to use in interactive programs because it 2011This is a very bad function to use in interactive programs because it
2009blocks, and a bad way to reduce concurrency because it is inexact: Better 2012blocks, and a bad way to reduce concurrency because it is inexact: Better
2010use an C<aio_group> together with a feed callback. 2013use an C<aio_group> together with a feed callback.
2011 2014
2012Its main use is in scripts without an event loop - when you want to stat 2015Its main use is in scripts without an event loop - when you want to stat
2013a lot of files, you can write somehting like this: 2016a lot of files, you can write something like this:
2014 2017
2015 IO::AIO::max_outstanding 32; 2018 IO::AIO::max_outstanding 32;
2016 2019
2017 for my $path (...) { 2020 for my $path (...) {
2018 aio_stat $path , ...; 2021 aio_stat $path , ...;
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2063some "Advanced I/O" function not available to in Perl, without going the 2066some "Advanced I/O" function not available to in Perl, without going the
2064"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> 2067"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
2065counterpart. 2068counterpart.
2066 2069
2067=over 4 2070=over 4
2071
2072=item $numfd = IO::AIO::get_fdlimit
2073
2074Tries to find the current file descriptor limit and returns it, or
2075C<undef> and sets C<$!> in case of an error. The limit is one larger than
2076the highest valid file descriptor number.
2077
2078=item IO::AIO::min_fdlimit [$numfd]
2079
2080Try to increase the current file descriptor limit(s) to at least C<$numfd>
2081by changing the soft or hard file descriptor resource limit. If C<$numfd>
2082is missing, it will try to set a very high limit, although this is not
2083recommended when you know the actual minimum that you require.
2084
2085If the limit cannot be raised enough, the function makes a best-effort
2086attempt to increase the limit as much as possible, using various
2087tricks, while still failing. You can query the resulting limit using
2088C<IO::AIO::get_fdlimit>.
2089
2090If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
2091true.
2068 2092
2069=item IO::AIO::sendfile $ofh, $ifh, $offset, $count 2093=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
2070 2094
2071Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, 2095Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
2072but is blocking (this makes most sense if you know the input data is 2096but is blocking (this makes most sense if you know the input data is

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