Re: Send_File API versus Send API over a Socket

[Scott Klement <rpg400-l@xxxxxxxxxxxxxxxx>]

Actually I *did* suggest that Shannon use read() in a prior message. 
However, I disagree with your assertion that fread is unsuitable.  It's 
not.  fread is intended for this type of thing.

The difference between read() and fread() has to do with their origin. 
read() is a system API -- a component of the operating system.  fread() 
is part of the ILE C runtime library.

read() comes from Unix and is intended to be available with the same 
syntax on all POSIX compliant systems (read: Unix systems).  i5/OS 
supports it as part of the "Unix-type APIs".  It is not part of the C 
language, however.  read() can be expected to exist on any compliant 
system, even if you don't have a C runtime installed on that system.

However, fread() is part of the C language.  Any system that supports 
ANSI C will always have an fread() function, even if it doesn't make any 
attempt to conform to POSIX.  For example, Windows has an fread() 
function, but not read().

So the difference isn't really what purpose their suited for -- the 
difference is what environment you're in.  Both functions are suitable 
for reading binary objects, including image files.  (However, fgets() is 
not -- and that was the original problem.)

In RPG on i5/OS, the distinction doesn't matter much to us, since both 
are always available.  If Shannon prefers to use fread(), let him use 
fread().


Lim Hock-Chai wrote:
> fread() function seems to be designed to read stream file where data in
> the file is segmented and, just like record in a database file, each
> segment has the same length.  Of course, by passing those parameters the
> way you suggested would allow Shannon to know the length of data that
> this api has read.  I'm just curious as why not just use the read()
> function.  This function seems to be a more suitable function to use
> when needing to read an image file.