Hi,

I've got a filename which contains some flags about the file stored as a bitstring. I can extract the bitstring from the filename, but I can't seem to work out how to test if a particular bit is set or not.

The files are stored as:
<filename>.<bitstring>
e.g. mymessage.1004

The definition for the different bits are:

FLAG_DELETED     0x0001
FLAG_DRAFT       0x0002
FLAG_SEEN        0x0004
FLAG_RECENT      0x0008
FLAG_FLAGGED     0x0010
FLAG_ANSWERED    0x0020
FLAG_SAVED       0x0040
FLAG_MDNSENT     0x0080
FLAG_STTPENDING  0x0100
FLAG_FAVOURITE   0x0200
FLAG_NOTIFY      0x0400
FLAG_STTPRESENT  0x0800
FLAG_STTCOMPLETE 0x1000

[download]

All integers are expressed in hex format. So if I have the following "1004", that means the SEEN flag and the STTCOMPLETE flag have been set.

I'm trying to test if the FAVOURITE flag has been set, but I don't really understand how to do it. I see posts online about unpacking the bits using the perl unpack function, but I'm not sure how to use it.

I'm sure this is trivial, but I'm still relatively new to perl and writing software, so please be kind.

In reply to How do I test if a bit has been set in a bitstring by willk1980

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