[Baypiggies] Is this a conversion problem? Can I get help to resolve this please?

[David Elsen]

Hi Joshua,

Got it. Thanks. I am misiing the "seek" part.

Thanks again,
David

On Tue, Aug 26, 2008 at 4:14 PM, Joshua Gallagher <
joshua.gallagher at gmail.com> wrote:

> Hi David,
>
> When you read and write into a file, you read and write at offsets.
> You can think of the offset as a moving cursor in the file.  In other
> words, if you create a new file and write 10 bytes in, your cursor is
> 10-bytes into the file.  If you perform another write, the write
> starts at byte 10.  By extension, if your cursor is at byte 10 of this
> new file and you do a read, there's nothing at the end of the file to
> read.
>
> If you've written to a file and want to reread it without closing it
> you need to seek (http://docs.python.org/lib/bltin-file-objects.html)
> if you have a file object or lseek
> (http://docs.python.org/lib/os-fd-ops.html) if you have a file
> descriptor.
>
> Joshua
>
>
>
> On Tue, Aug 26, 2008 at 3:56 PM, David Elsen <elsen.david08 at gmail.com>
> wrote:
> > Alex,
> >
> > Thank you for your reply.
> >
> > Actually I had modified the text file before posting. It has four words
> in
> > one line seperated by space.  I was using the split with  space to get
> all
> > four words from a line. I was appending one word to my list (list of
> > strings).
> >
> > I was wondering once I am using split function whether it converts the
> > "numbers" from my text file to some particular formats. I was trying to
> cast
> > the split output with "map", "long" etc, but it gives the error message
> > that for it can not accept the non-string input.
> >
> > I tried to look around for split reference, but nowhere got its return
> type
> > format information. It seems like string ['0xdeadfeed']. But it does not
> > seem to be. If it is really string type, why cast from "map", "int", or
> > "long" is giving me error message.
> >
> > I apologize for becoming the time sink. I am ready to become the time
> > source.
> >
> > I have one more question though related to my same script. Please forgive
> me
> > about this. If I am trying to write my text file in the same script and
> then
> > tring to read back. For some reason, read file handle does not have any
> > data.
> >
> > But if I have written to the text file and saved it and then trying to
> open
> > it in read mode, I am able to read the data. Is there any delay required
> > after writing the data to a file?
> >
> > Thanks,
> > David
> >
> > Thanks again,
> > David
> >
> >
> >
> >
> >
> >
> > On Tue, Aug 26, 2008 at 1:26 PM, Alex Martelli <aleax at google.com> wrote:
> >>
> >> You should really study some of the basics of Python -- e.g. via the
> >> mailing list http://mail.python.org/mailman/listinfo/tutor or any of
> >> the other resources listed at
> >> http://wiki.python.org/moin/BeginnersGuide -- this mailing list is for
> >> the Bay Area Python Interest Group and not particularly suitable for
> >> your questions.  In this case, you're appending to your list reg items
> >> that are lists of strings (with one item only in each sublist,
> >> apparently) and you apparently want to convert that list of lists of
> >> strings to a list of integers -- and give no indication whatsoever
> >> about what you mean to happen when one of the sublists has more than
> >> one item (i.e. any of the text lines in file ask_it.txt [apart from
> >> the first four] has more than one word), or any of the words are not a
> >> correct representation for an integer, and so forth.  If you know the
> >> "more than one word in a line" can never happen, then it makes no
> >> sense to have that "datas = line.split()" call -- why are you
> >> splitting unless >1 word is possible?!
> >>
> >> http://www.catb.org/~esr/faqs/smart-questions.html is a document
> >> really worth studying (quite apart from Python, ANY time you need to
> >> ask technical questions) and it includes worthy quotes such as "What
> >> we are, unapologetically, is hostile to people who seem to be
> >> unwilling to think or to do their own homework before asking
> >> questions. People like that are time sinks — they take without giving
> >> back, and they waste time we could have spent on another question more
> >> interesting and another person more worthy of an answer."
> >>
> >>
> >> Alex
> >>
> >> On Tue, Aug 26, 2008 at 1:02 PM, David Elsen <elsen.david08 at gmail.com>
> >> wrote:
> >> > Hi all,
> >> >
> >> > I have a test script as follows:
> >> >
> >> > import os
> >> > import string
> >> > cmd = './testtool  dump'
> >> > res = os.popen(cmd).read()
> >> > #print res
> >> > #fout = open("ask_it.txt", "w")
> >> > #fout.write(res)
> >> > #fout.close
> >> > reg_reset_val = []
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> > reg_reset_val.append(0xdeadfeed)
> >> >
> >> > print 'reg default values'
> >> > for index, item in enumerate(reg_reset_val):
> >> >  print index, item
> >> >
> >> > fin = open ("ask_it.txt", "r")
> >> > i = 0
> >> > reg = []
> >> > linelist = fin.readlines()
> >> > lines = len(linelist)
> >> > for line in linelist:
> >> >  i = i +1
> >> >  if (i >= 5): # First four lines are bogus
> >> >   datas = line.split()
> >> >   reg.append(datas)
> >> >   if i == lines:
> >> >    break
> >> > print 'the reg list is'
> >> > for j, item in enumerate(reg):
> >> >  print j, item
> >> > print 'reg[0]'
> >> > print reg[0]
> >> > print 'reg_reset_val[0]0x%x'%reg_reset_val[0]
> >> > #print reg_reset_val[0]
> >> > if (reg[0] == reg_reset_val[0]):
> >> >  print 'test passed'
> >> > else:
> >> >  print 'test failed'
> >> >
> >> >
> >> > Calling to driver via IOCTL Control Memory Dump buf addr = 0x804d008.
> >> > Returned from calling driver via IOCTL.
> >> > IOCTL CTL Mem Dump char count
> >> > Control Memory Dump:  Address 0xf8812000
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > 0xdeadfeed
> >> > I am expecting the "reg[0]" and "reg_reset_val[0]" to be the same. But
> >> > reg[0] is list and has ['0xdeadfeed'] in it and reg_reset_val[0] has
> >> > 0xdeadfeed in it. How can I convert the reg[0] to make it normal
> >> > 0xdeadfeed.
> >> >
> >> > Thanks,
> >> > David
> >> >
> >> >
> >> >
> >> > _______________________________________________
> >> > Baypiggies mailing list
> >> > Baypiggies at python.org
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> >> > http://mail.python.org/mailman/listinfo/baypiggies
> >> >
> >
> >
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