Re: question about nullptr

On 8/25/24 4:55 PM, dave_thompson_2@comcast.net wrote:

On Mon, 15 Jul 2024 19:49:08 -0400, James Kuyper
<jameskuyper@alumni.caltech.edu> wrote:
 

On 7/15/24 18:51, Lawrence D'Oliveiro wrote:

[silliness]

Keep in mind that, in text mode, the <stdio.h> library routines use '\n'
in memory to represent whatever platform-specific method is used in
files to indicate a new line. For example, that can be a simple '\n' on
typical Unix-like machines, '\n\r' or '\r\n' on other operating systems,
and on a number of older systems, it could be converted to and from a
fixed-size block with a character count at the the beginning of the
block. There's no requirement that it be the Unicode line feed character.

 I never knew any older system that used a fixed-size block (or rather
record, which in those days was not the same as block) AND prefix
count in the same file, although OS/360 et seq used ONE of them.
 And Tandem Enscribe used either offset or count fields (depending on
structure) at _end_ of block, near but not adjacent to records, except
for textfiles had prefix counts per line AND word (of nonblanks) --
but the initial versions of their C implementation couldn't handle
textfiles, so you had to convert them to and from 'data'.

The systems that I used that needed that ability didn't put a length at the beginning of each block, but ALL the blocks were a fixed size in length (perhaps 80 characters) and shorter records were just filled out with spaces after the data (thus, the records were images of the 80 column punched cards that would always have 80 columns of data).