From: paul.winalski@gmail.com (Paul Winalski)
Subject: [TUHS] origin of C header files
Date: Fri, 29 Dec 2017 14:28:06 -0500 [thread overview]
Message-ID: <CABH=_VTZLbJjgidBL92PpyYTXsA8zwbBsfeMqkA=kaam-E5rEA@mail.gmail.com> (raw)
In-Reply-To: <CACNPpeYw3maUqXr8NxotW9FZMjhJmm-K9kEv2ma6SytiQB=1cg@mail.gmail.com>
On 12/29/17, Wesley Parish <wobblygong at gmail.com> wrote:
>
> Which raised the question: when did header files come into use? Who
> was the first to use header files to store common system-wide or
> application-wide data definitions? Was it used in any languages prior
> to C?
It probably all started with macro-instructions (macros) in assembly
languages. The assembler for System/360 in the 1960s had a pretty
complex and powerful conditional assembly and macro expansion
capability. That technology I'm sure dates back to the 1950s.
When higher-level languages came along, programmers moving from
assembly code to a HLL would want the same sort of preprocessor
functionality. I know that IBM PL/I had %include, and I suspect that
other HLLs of the day had similar features.
What's very clear is that C did not invent include files or
conditional compilation, it merely carried on existing tradition.
-Paul W.
next prev parent reply other threads:[~2017-12-29 19:28 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-29 8:26 Wesley Parish
2017-12-29 10:58 ` Nigel Williams
2017-12-29 19:28 ` Paul Winalski [this message]
2017-12-29 20:31 ` Clem Cole
2017-12-30 1:06 ` Steve Johnson
2017-12-30 1:52 ` Paul Winalski
2018-01-23 4:27 ` Steve Johnson
2017-12-31 2:32 Doug McIlroy
2018-01-12 8:44 Lars Brinkhoff
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