what's the sizeof...unpack('H or h or B or b ? 
Author Message
 what's the sizeof...unpack('H or h or B or b ?

i have a data file that i need to modify.  here are some lines from xdump:
================
00000000    00000000 00000000 00000000 00000000    ................
00000010    0000f333 41349a33 41340f34 7b33b733    ...3A4.3A4.4{3.3
00000020    3e35f134 cb347534 5c35a034 0f341234    >5.4.4u4\5.4.4.4
00000030    b733c933 df34b334 b334e534 70344134    .3.3.4.4.4.4p4A4
00000040    8b349434 94349434 0435f134 92354d35    .4.4.4.4.5.4.5M5
00000050    bf352d35 f134f134 2d353e35 3e353e35    .5-5.4.4-5>5>5>5
==================
looks to me that the bytes are in the wrong order, that is, instead
of F333(62,259 dec), the pattern should be 33F3(13,299 dec).

  foolish me, i thought dd would swab the bytes.

i have been trying to use the source of xdump to do this byte swapping,

i can pull apart each original value (F333):

     while (($len = read(STDIN,$data,2)) == 2) {

seems to work, but have not been able to break apart this n value.

also, it looks to me, that the while line is grabbing two full bytes,
yet, i seem to be able to use unpack('n'  to isolate each value.

any info?

thanx,
roger hubbard
--


Geography-Geology Department
University of Nebraska at Omaha



Sat, 15 Mar 1997 22:31:23 GMT  
 
 [ 1 post ] 

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