On Tuesday, November 04, 2014 20:12:21 Sativa via Digitalmars-d-learn wrote:
> Is there a very easy way to search a file for a string, then
> extract to a new file everything from that match on to the end of
> the file?
>
> I basically want to remove a header from a file(it's length is
> not fixed though).
>
> It seems I'm having to convert bytes to chars to strings and back
> and all that mess, which is not very elegant.
By far the easiest would be something like
import std.algorithm;
import std.file;
auto fileContents = std.file.readText("filename");
auto found = fileContents.find(stringImLookingFor);
std.file.write("filename", found);
though that requires reading the entire file into memory at once. If you're
dealing with a text file, that probably isn't a problem though, and any
sane alternatives would require writing to a new file and then moving that
file to replace the old one, which is more involved. But std.stdio.File and
std.stdio.File.byLine can be used to read the file one line at a time, in
which case you'd just not write any of the lines until you found a line with
the string that you were looking for, in which case you'd write the part of
the line that you wanted to a file, and then write every line after that to
the file. Or you could use std.mmfile.MmFile to read the whole file as a
memory buffer, use find on that to find the portion that you want and then
write it to disk (probably with std.file.write), but that definitely
requires some casting and probably only makes sense if you want to be able
to use find on the whole file at once without necessarily bringing the
entire file into memory at once. Personally, I'd just use std.file.readText
and std.file.write though. It's simple, and it would only be a problem if
you were dealing with a very large file (which text files normally aren't).
- Jonathan M Davis
