Description:
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AIX and Linux behaves differently when using file functions with regular filenames containing an excedentary trailing slash.

Linux raises an error in this case, as expected in the Open Group specifications, while AIX ignores the trailing slash.

To ensure consistent behaviour on the two OS, I suggest to add a check for excendentary trailing slash when accessing a regular file on AIX, and to raise the same error as on Linux. This is implemented in the attached patch (tested with PHP 7.0.3, 7.0.7, 7.0.9 and 7.0.10 on AIX 6.1).

If consistency is not a priority, some tests under ext/standard/tests/file will need to be skipped on AIX (or better, the trailing slash tests should be grouped in a single phpt file, skipped on AIX, so that the other file related tests won't be skipped) : filegroup_variation3.phpt, fileinode_variation3.phpt, fileowner_variation3.phpt, fileperms_variation3.phpt and ext/standard/tests/file/rename_variation.phpt