file magic for mprime save files

[geoff]

From the mprime source code I see that the save files for ECM and P-1 tests have a magic number, so I have made the following entries for /etc/magic so the 'file' program will recognise them:

#
# ECM save file eNNNNNNN
#
0	ulong	0x1a2b3cd4	Prime95 ECM data,
>4	ulong	x		version %lu,
>24	ulong	x		B1=%lu,
>12	ulong	x		curve #%lu,
>8	ulong	0		in stage 1,
>>28	ulong	x		at prime %lu
>8	ulong	1		in stage 2,
>>32	ulong	x		at prime %lu
#
# P-1 save file mNNNNNNN
#
0	ulong	0x1a2b3c4d	Prime95 P-1 data,
>4	ulong	x		version %lu,
>16	ulong	x		B1=%lu,
>28	ulong	>0		B2=%lu,
>8	ulong	0		in stage 1
>8	ulong	1		in stage 2
>8	ulong	2		complete
>8	ulong	3		in stage 1

There is more information in the files that would be nice to be able to extract, such as actual P-1 progress rather than just which stage it is in, but I am not sure how to do it with 'magic' format. This is an example of the output from file:

$ file e0001522 
e0001522: Prime95 ECM data, version 1, B1=44000000, curve #152, in stage 2, at prime 453577741