darckness000 wrote: > I'm trying to read line-feed (ASCII #10) terminated lines from a file > (think UNIX file), not the usual CRLF (ASCII #13 #10) terminated > lines. > > What I'm doing at the moment is to `Read' 1 char at a time into a var > until I hit an LF + then display the string to the user. While this > works, it is sloooowwwwwwwwww when seeking to the last line in a > large file.
If you want the last line, then maybe you could read backward from the end of the file. > I've tried using `Read' with zero based character arrays - + while > this is much faster, read fills the array completely (ie: if the > array is [0..999], Read will read 1000 chars from the file) instead > of stopping at the LF in the file. As each line in the file is > variable in length, I am unable to allocate a static array. Dynamic > arrays don't work with `Read', but as I don't the length of each > string in the file this doesn't really matter. You know, that's exactly what ReadLn does. But when it reaches the end of a line, it keeps the remainder of the buffer around to use for the next line. > When comparing speed against what I'm currently doing + using ReadLn > (ReadLn doesn't read the LF, I was just testing speed), ReadLn is so > much quicker it's unbelievable. Based on my reading of the Delphi 2005 code, it's the line feed that makes ReadLn stop reading. Merely a carriage return is _not_ sufficient for ending a line. They do not mark the end of a line, and they are not copied into the result buffer. What version are you using? > My question is, does anyone know of a way to read LF terminated lines > from a file with speed comparable to ReadLn? TStrings.LoadFromFile handles all sorts of line-end styles. If you can afford to load the entire file into memory. -- Rob
