Fastest way to remove the first x characters from a very long string

[bruceg113355 at gmail.com]

On Saturday, May 16, 2015 at 11:13:45 AM UTC-4, Rustom Mody wrote:
> On Saturday, May 16, 2015 at 8:30:02 PM UTC+5:30, Grant Edwards wrote:
> > On 2015-05-16, bruceg113355 wrote:
> > 
> > > I have a string that contains 10 million characters.
> > >
> > > The string is formatted as:
> > >
> > > "0000001 : some hexadecimal text ... \n
> > > 0000002 : some hexadecimal text ... \n
> > > 0000003 : some hexadecimal text ... \n
> > > ...
> > > 0100000 : some hexadecimal text ... \n
> > > 0100001 : some hexadecimal text ... \n"
> > >
> > > and I need the string to look like:
> > >
> > > "some hexadecimal text ... \n
> > > some hexadecimal text ... \n
> > > some hexadecimal text ... \n
> > > ...
> > > some hexadecimal text ... \n
> > > some hexadecimal text ... \n"
> > >
> > > I can split the string at the ":" then iterate through the list
> > > removing the first 8 characters then convert back to a string. This
> > > method works, but it takes too long to execute.
> > >
> > > Any tricks to remove the first n characters of each line in a string faster?
> > 
> > Well, if the strings are all in a file, I'd probably just use sed:
> > 
> > $ sed 's/^........//g' file1.txt >file2.txt
> > 
> > or
> > 
> > $ sed 's/^.*://g' file1.txt >file2.txt
> 
> 
> And if they are not in a file you could start by putting them (it) there :-)
> 
> Seriously... How does your 'string' come into existence?
> How/when do you get hold of it?

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