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+README for Android "acp" Command
+
+The "cp" command was judged and found wanting. The issues are:
+
+Mac OS X:
+ - Uses the BSD cp, not the fancy GNU cp. It lacks the "-u" flag, which
+ only copies files if they are newer than the destination. This can
+ slow the build when copying lots of content.
+ - Doesn't take the "-d" flag, which causes symlinks to be copied as
+ links. This is the default behavior, so it's not all bad, but it
+ complains if you supply "-d".
+
+MinGW/Cygwin:
+ - Gets really weird when copying a file called "foo.exe", failing with
+ "cp: skipping file 'foo.exe', as it was replaced while being copied".
+ This only seems to happen when the source file is on an NFS/Samba
+ volume. "cp" works okay copying from local disk.
+
+Linux:
+ - On some systems it's possible to have microsecond-accurate timestamps
+ on an NFS volume, and non-microsecond timestamps on a local volume.
+ If you copy from NFS to local disk, your NFS files will always be
+ newer, because the local disk time stamp is truncated rather than
+ rounded up. This foils the "-u" flag if you also supply the "-p" flag
+ to preserve timestamps.
+ - The Darwin linker insists that ranlib be current. If you copy the
+ library, the time stamp no longer matches. Preserving the time
+ stamp is essential, so simply turning the "-p" flag off doesn't work.
+
+Futzing around these in make with GNU make functions is awkward at best.
+It's easier and more reliable to write a cp command that works properly.
+
+
+The "acp" command takes most of the standard flags, following the GNU
+conventions. It adds a "-e" flag, used when copying executables around.
+On most systems it is ignored, but on MinGW/Cygwin it allows "cp foo bar"
+to work when what is actually meant is "cp foo.exe bar.exe". Unlike the
+default Cygwin cp, "acp foo bar" will not find foo.exe unless you add
+the "-e" flag, avoiding potential ambiguity.
+