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FileCache - keep more files open than the system permits


use FileCache;
# or
use FileCache maxopen => 16;

cacheout $path;
print $path @data;

cacheout $mode, $path;
print $path @data;


The cacheout function will make sure that there's a filehandle open for reading or writing available as the pathname you give it. It automatically closes and re-opens files if you exceed your system's maximum number of file descriptors, or the suggested maximum.

cacheout EXPR

The 1-argument form of cacheout will open a file for writing ('>') on it's first use, and appending ('>>') thereafter.

cacheout MODE, EXPR

The 2-argument form of cacheout will use the supplied mode for the initial and subsequent openings. Most valid modes for 3-argument open are supported namely; '>', '+>', '<', '<+', '>>', '|-' and '-|'


If you use cacheout with '|-' or '-|' you should catch SIGPIPE and explicitly close the filehandle., when it is closed from the other end some cleanup needs to be done.

While it is permissible to close a FileCache managed file, do not do so if you are calling FileCache::cacheout from a package other than which it was imported, or with another module which overrides close. If you must, use FileCache::cacheout_close.


sys/param.h lies with its NOFILE define on some systems, so you may have to set maxopen ($FileCache::cacheout_maxopen) yourself.

1 POD Error

The following errors were encountered while parsing the POD:

Around line 42:

You forgot a '=back' before '=head1'