On Mon, May 25, 2009 at 1:32 AM, xbmuncher <[email protected]> wrote: > I've been reading about ways to convert strings and what not to hex and back > and forth. I'm looking for the fastest and least memory intensive way to > search through a file for a hex value and gets its byte offset in the file. > This hex value (that I'm looking for in the file) is of course a hex > representation of the binary data and its 8 bytes long. > I figured reading the whole file and converting it to hex from ascii..etc.. > would be overkill, especially if its a large file. > What do you guys recommend? I want to search the file for certain hex value > and get the byte offset within the file. > > Thanks for reading.
If the input is a text file containing hex strings, then: * compile a regular expression for a hex string using the re module * initialize a byte count for previous lines to 0 * read the input file line by line ** search each line for the compiled regular expression *** for each hit found **** output a file offset based on the byte count and offset within the line ** add the length of the line to a running total of the number of bytes in the previous lines Is that what you are looking for? -- Walker Hale <[email protected]> _______________________________________________ Tutor maillist - [email protected] http://mail.python.org/mailman/listinfo/tutor
