From Newsgroup: comp.lang.c

ok if someone want regular c stuff
(there still are some parts of c i dont learned (i got no tiem as they
vere rarely used)it is this variadic stuff

i once seen it like maybe outdated/obsolete/archaic stuff but in fact
i had probably normie mind in this point - becouse later i discovered
that this printf is not such bad in practice (im not sure if i would
name it very good but if back then i got a view that my apps shouldnt
use it and maybe i should use my own separate routines for printing text
and numbers it showed to be more annoying (those print("ss");
printN(23); print("aassaaas"); ) than printf

but im not fully comprehending this varargs stuff and i think i should
learn it (though its panful for old 50 year old man)

so the question is the passing down the variadic arguments costly?

how it work?

i mean when you got function that takes varargs like

void slog_yellow(char *format, ...)
{
SlogColor(0xffff00); va_list args; va_start(args, format); slog(format, args); va_end(args);

}

and you pass it down to oryginal slog() which also takes varargs

void slog_(char *format, ...)
{
va_list args;
va_start(args, format);
int n = vsnprintf(&slog_[slog_top][0], slog_line_max, format, args);
va_end(args);


slog_top++;
}

which in turn as uit shows passes it down to vsnprintf

does this passing is costly?


as i dont understand this well in fact i may make some errors codng it
(but as i said up the point i was not much fiery reasons to learn this)

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From Newsgroup: comp.lang.c

fir pisze:

ok if someone want regular c stuff
(there still are some parts of c i dont learned (i got no tiem as they
vere rarely used)it is this variadic stuff

i once seen it like maybe outdated/obsolete/archaic stuff but in fact
i had probably normie mind in this point - becouse later i discovered
that this printf is not such bad in practice (im not sure if i would
name it very good but if back then i got a view that my apps shouldnt
use it and maybe i should use my own separate routines for printing text
and numbers it showed to be more annoying (those print("ss");
printN(23);-a print("aassaaas"); ) than printf

but im not fully comprehending this varargs stuff and i think i should
learn it (though its panful for old 50 year old man)

so the question is the passing down the variadic arguments costly?

how it work?

i mean when-a you got function that takes varargs like

-avoid slog_yellow(char *format, ...)
-a{
-a-a-a SlogColor(0xffff00);-a-a-a va_list args; va_start(args, format); slog(format, args);-a-a-a va_end(args);

-a}

and you pass it down to oryginal slog() which also takes varargs

void slog_(char *format, ...)
-a{
-a-a-a-a-a va_list args;
-a-a-a-a-a va_start(args, format);
-a-a-a-a int n =-a vsnprintf(&slog_[slog_top][0], slog_line_max, format, args);
-a-a-a-a-a va_end(args);

-a-a-a-aslog_top++;
}

which in turn as uit shows passes it down to vsnprintf

does this passing is costly?

as i dont understand this well in fact i may make some errors codng it
(but as i said up the point i was not much fiery reasons to learn this)

(the example here may be seen nonsense as i pass a color value than not
use it but i jost got the slog updated to store colors alos in its ram
to be ablo to write color mesages but skipped it for clarity of
question, maybe i should put //.. there)
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From Newsgroup: comp.lang.c

On 11/09/2026 12:25, fir wrote:

ok if someone want regular c stuff
(there still are some parts of c i dont learned (i got no tiem as they
vere rarely used)it is this variadic stuff

i once seen it like maybe outdated/obsolete/archaic stuff but in fact
i had probably normie mind in this point - becouse later i discovered
that this printf is not such bad in practice (im not sure if i would
name it very good but if back then i got a view that my apps shouldnt
use it and maybe i should use my own separate routines for printing text
and numbers it showed to be more annoying (those print("ss");
printN(23);-a print("aassaaas"); ) than printf

but im not fully comprehending this varargs stuff and i think i should
learn it (though its panful for old 50 year old man)

so the question is the passing down the variadic arguments costly?

how it work?

i mean when-a you got function that takes varargs like

-avoid slog_yellow(char *format, ...)
-a{
-a-a-a SlogColor(0xffff00);-a-a-a va_list args; va_start(args, format); slog(format, args);-a-a-a va_end(args);

-a}

and you pass it down to oryginal slog() which also takes varargs

void slog_(char *format, ...)
-a{
-a-a-a-a-a va_list args;
-a-a-a-a-a va_start(args, format);
-a-a-a-a int n =-a vsnprintf(&slog_[slog_top][0], slog_line_max, format, args);
-a-a-a-a-a va_end(args);

-a-a-a-aslog_top++;
}

which in turn as uit shows passes it down to vsnprintf

does this passing is costly?

Pass it through a preprocessor (-E option on many compilers) to see what
those va-macros expand to.

As for efficiency, that will depend on compiler; some may inline such
code for example.

But if performing output that also involves binary to text conversion,
that's already a bottleneck anyway.

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From Newsgroup: comp.lang.c

bart pisze:

On 11/09/2026 12:25, fir wrote:

ok if someone want regular c stuff
(there still are some parts of c i dont learned (i got no tiem as they
vere rarely used)it is this variadic stuff

i once seen it like maybe outdated/obsolete/archaic stuff but in fact
i had probably normie mind in this point - becouse later i discovered
that this printf is not such bad in practice (im not sure if i would
name it very good but if back then i got a view that my apps shouldnt
use it and maybe i should use my own separate routines for printing
text and numbers it showed to be more annoying (those print("ss");
printN(23);-a print("aassaaas"); ) than printf

but im not fully comprehending this varargs stuff and i think i should
learn it (though its panful for old 50 year old man)

so the question is the passing down the variadic arguments costly?

how it work?

i mean when-a you got function that takes varargs like

-a-avoid slog_yellow(char *format, ...)
-a-a{
-a-a-a-a SlogColor(0xffff00);-a-a-a va_list args; va_start(args, format); >> slog(format, args);-a-a-a va_end(args);

-a-a}

and you pass it down to oryginal slog() which also takes varargs

void slog_(char *format, ...)
-a-a{
-a-a-a-a-a-a va_list args;
-a-a-a-a-a-a va_start(args, format);
-a-a-a-a-a int n =-a vsnprintf(&slog_[slog_top][0], slog_line_max, format, >> args);
-a-a-a-a-a-a va_end(args);


-a-a-a-a-aslog_top++;
}

which in turn as uit shows passes it down to vsnprintf

does this passing is costly?

Pass it through a preprocessor (-E option on many compilers) to see what those va-macros expand to.

As for efficiency, that will depend on compiler; some may inline such
code for example.

But if performing output that also involves binary to text conversion, that's already a bottleneck anyway.

you could eventuall do that if its quick to do it for you..i may do it
but only later...im also not only for checking but also for discussing


(people falsely assume OFTEN (and its annoys me) that checking is the
same or better than discussing somethin - those are two separate things, discussing gived deeper orentation/understanding)
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From Newsgroup: comp.lang.c

On Fri, 11 Sep 2026 13:25:03 +0200, fir wrote:

but im not fully comprehending this varargs stuff and i think i
should learn it (though its panful for old 50 year old man)

DonrCOt worry about the internals of how it works, since that will very
much be architecture-specific. Just learn to use it, which is
basically quite simple. Just overlook the fact that itrCOs a gigantic
hole in the safenessrCa of the C type system.

One thing I have done is create Python wrappers around varargs calls
which can indeed be fully type-safe. This can be done entirely in
Python, without writing any C code, thanks to this wonderful library
module for creating wrappers, called ctypes <https://docs.python.org/3/library/ctypes.html>.

rCaHAHAHA etc
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From Newsgroup: comp.lang.c

Lawrence DrCOOliveiro wrote:

On Fri, 11 Sep 2026 13:25:03 +0200, fir wrote:

but im not fully comprehending this varargs stuff and i think i
should learn it (though its panful for old 50 year old man)

DonrCOt worry about the internals of how it works, since that will very
much be architecture-specific. Just learn to use it, which is
basically quite simple. Just overlook the fact that itrCOs a gigantic
hole in the safenessrCa of the C type system.

One thing I have done is create Python wrappers around varargs calls
which can indeed be fully type-safe. This can be done entirely in
Python, without writing any C code, thanks to this wonderful library
module for creating wrappers, called ctypes <https://docs.python.org/3/library/ctypes.html>.

rCaHAHAHA etc

Maybe he is referring to a phenomenon I've encountered while working with C:

It doesn't take much effort to learn a new C concept, WHEN, I need to
use it.

But there are lots out there and this isn't getting the job done of
"learning the whole language", as I haven't found the call to use
everything yet.

Not to mention a certain drift backwards during vacations.

Any suggestions? Perhaps just to keep pushing it even when I'm not so inclined?
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From Newsgroup: comp.lang.c

Lawrence DrCOOliveiro pisze:

On Fri, 11 Sep 2026 13:25:03 +0200, fir wrote:

but im not fully comprehending this varargs stuff and i think i
should learn it (though its panful for old 50 year old man)

DonrCOt worry about the internals of how it works, since that will very
much be architecture-specific. Just learn to use it, which is
basically quite simple. Just overlook the fact that itrCOs a gigantic
hole in the safenessrCa of the C type system.

One thing I have done is create Python wrappers around varargs calls
which can indeed be fully type-safe. This can be done entirely in
Python, without writing any C code, thanks to this wonderful library
module for creating wrappers, called ctypes <https://docs.python.org/3/library/ctypes.html>.

rCaHAHAHA etc

ok it showed not so hard

for example implementation of

varar("iicffd", 1, 2, 'a', 9.f, 8.5f, 10.0);

which may be simple implementation/interface of many cases of usage of
this whowed to be (ai)

#include <stdio.h>
#include <stdarg.h>

void varar(const char *types, ...)
{
va_list ap;
va_start(ap, types);

while(*types) {
switch(*types) {
case 'i': printf("%d\n", va_arg(ap, int)); break;
case 'c': printf("%c\n", va_arg(ap, int)); break;
case 'f': printf("%f\n", (double)va_arg(ap, double)); break;
case 'd': printf("%f\n", va_arg(ap, double)); break; }
types++; }

va_end(ap);
}
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From Newsgroup: comp.lang.c

On Sun, 13 Sep 2026 11:17:41 +0200, fir wrote:

Lawrence DrCOOliveiro pisze:

One thing I have done is create Python wrappers around varargs
calls which can indeed be fully type-safe.

ok it showed not so hard

for example implementation of

varar("iicffd", 1, 2, 'a', 9.f, 8.5f, 10.0);

This is where dynamically-typed languages have the edge.
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