Systems software versus applications software definitions

[Matt]

How do we define systems programs? when we say systems programming,
does it necessary mean that the programs we write need to interact
with hardware directly? For example, OS, compiler, kernel, drivers,
network protocols, etc...? Couple years ago, yes, I understand this is
definitely true. However, as the software applications become more and
more complicated, some people try to argue that. Some people argue the
definition of systems programs depend on the level of abstractions. I
heard people saying that web server is a systems software, which I
feel confused. I think web server is an application software. Yes,
other applications run on top of web server.

Please advise and discuss. thanks!!

[Gordon Burditt]

>How do we define systems programs?

comp.lang.c does not.

when we say systems programming,
does it necessary mean that the programs we write need to interact
with hardware directly?
That term does not have a precise definition and there is not
a sharp line between systems and applications programming.
The line gets particularly fuzzy when you are talking about
computers embedded into other devices, like cell phones.

No, I'd consider a lot of the low-level network stuff like the
TCP stack to be systems programming, even if it's not specific
to a particular type of network hardware (and there may not BE
any specific network hardware beyond a serial port. There are
also "tunnel drivers" which have a network stack but don't
actually use any hardware at all).
For example, OS, compiler, kernel, drivers,
network protocols, etc...? Couple years ago, yes, I understand this is
definitely true. However, as the software applications become more and
more complicated, some people try to argue that.
Some people argue the
definition of systems programs depend on the level of abstractions. I
heard people saying that web server is a systems software, which I
feel confused.
The video driver in Microsoft Windows probably calls Internet
Explorer to actually access the hardware :-( In any case, Microsoft
claims IE is so tightly bound into the OS you can't remove it.
I think they said that under oath in court, too.
I think web server is an application software. Yes,
other applications run on top of web server.

I consider the web server in my VOIP terminal adapter to be systems
programming, in large part because it is burned into flash and is
used to configure the adapter. The same thing applies to the Web
Management Card (which runs a web server, SNMP server, and a few
other things) that plugs into my APC UPS, for much the same reason.

On the other hand, Apache running on my PC I consider to be an
application (which, as you said, has other applications running
under it, like PHP and under that various web pages which do various
things, like present an index of my CD collection.)

Gordon L. Burditt

[Matej Barac]

On 24 Nov 2004 16:00:55 -0800, Matt wrote:

How do we define systems programs? when we say systems programming,
does it necessary mean that the programs we write need to interact
with hardware directly? For example, OS, compiler, kernel, drivers,
network protocols, etc...? Couple years ago, yes, I understand this is
definitely true. However, as the software applications become more and
more complicated, some people try to argue that. Some people argue the
definition of systems programs depend on the level of abstractions. I
heard people saying that web server is a systems software, which I
feel confused. I think web server is an application software. Yes,
other applications run on top of web server.

Please advise and discuss. thanks!!

I personally would say programming an application is getting easier with
time (C#, Java, VB,...). Hardly anyone still bothers with Assembly...

On the topic, for me a system program is the one that either a) interact
with the hardware directly (and are written on a very low level) or b)
interacts with the OS on a low level (PartitonMagic for example).

[Matej Barac]

On 25 Nov 2004 00:26:42 GMT, Gordon Burditt wrote:

The video driver in Microsoft Windows probably calls Internet
Explorer to actually access the hardware :-( In any case, Microsoft
claims IE is so tightly bound into the OS you can't remove it.
I think they said that under oath in court, too.

Kind of off topic, but... IE can be "safely" removed from the OS.

[dandelion]

"Matej Barac" <ma*********@gm ail.com> wrote in message
news:1n******** *************** ******@40tude.n et...

On 24 Nov 2004 16:00:55 -0800, Matt wrote:
<snip>
I personally would say programming an application is getting easier with
time (C#, Java, VB,...). Hardly anyone still bothers with Assembly...

Unless, of course you are into embedded software, where it's (on a regular
basis) neccesary in order to implement ISR's (for one instance). Also
implementing support for many CPU/HW features can hardly do without.

<snip>

[Maxim S. Shatskih]

> The video driver in Microsoft Windows probably calls Internet

Explorer to actually access the hardware :-( In any case, Microsoft
claims IE is so tightly bound into the OS you can't remove it.
I think they said that under oath in court, too.

Correct. The Windows shell (the code which manages the taskbar, start menu,
file folder windows and things like My Computer window) is hardly linked to
MSHTML and is dependent on it.

As about "system" vs. "app" level development - I would jugde from the
practical standpoint of a) tools used b) stability requirements. From such
point of view, all embedded code is system one :)

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
ma***@storagecr aft.com
http://www.storagecraft.com

[Maxim S. Shatskih]

> Kind of off topic, but... IE can be "safely" removed from the OS.

No.

You can install another browser and use it as a default handler for URLs.
Nothing more. Help files, shell folders and lots of new-fashion XP's UI are
still shown by MSHTML.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
ma***@storagecr aft.com
http://www.storagecraft.com

[CTips]

Matt wrote:

How do we define systems programs? when we say systems programming,
does it necessary mean that the programs we write need to interact
with hardware directly? For example, OS, compiler, kernel, drivers,
network protocols, etc...? Couple years ago, yes, I understand this is
definitely true. However, as the software applications become more and
more complicated, some people try to argue that. Some people argue the
definition of systems programs depend on the level of abstractions. I
heard people saying that web server is a systems software, which I
feel confused. I think web server is an application software. Yes,
other applications run on top of web server.

Please advise and discuss. thanks!!

I'd say that system software generally shares the following characteristics :
- its performance sensitive
- it has some dependence on hardware
Now, kernel + compiler definitely satisfy both these two requirements,
network protocol stacks mostly the first, drivers mostly the second.

[Jan Vorbrüggen]

> I'd say that system software generally shares the following

characteristics :
- its performance sensitive
- it has some dependence on hardware

I would disagree. For me system software is more or less equivalent to
being part of the trusted computing base, with the more or less implied
side effect that if something unexpected goes wrong with it, you need to
crash the system. Handling hardware is only part of that, and there are
scenarios where you can have software driving hardware directly without
being part of the TCB - rare, but it has happened. Performance - sure,
you would want that, but correctness is top priority. As a counterpoint,
how many OSs have you seen that have been compiled with optimization for
the particular processor model they will run on?

Jan

[Matt]

Hi Matt, I'm Matt too,

Great question, I always wondered that too. I met an embedded programmer in
San Diego years ago. He said the more down to the hardware level he got, the
more exciting it was. Also maybe somebody could explain this, I've seen a
lot of mainframe positions advertised as "system programmer"

Matt

"Matt" <jr********@hot mail.com> wrote in message
news:ba******** *************** ***@posting.goo gle.com...

How do we define systems programs? when we say systems programming,
does it necessary mean that the programs we write need to interact
with hardware directly? For example, OS, compiler, kernel, drivers,
network protocols, etc...? Couple years ago, yes, I understand this is
definitely true. However, as the software applications become more and
more complicated, some people try to argue that. Some people argue the
definition of systems programs depend on the level of abstractions. I
heard people saying that web server is a systems software, which I
feel confused. I think web server is an application software. Yes,
other applications run on top of web server.

Please advise and discuss. thanks!!