Hi
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
Thanks,
Leon
10  9951 
On 27 Nov 2003 19:18:11 -0800, io****@yahoo.co m (ios) wrote: Hi
Can someone tell me what is different between below case?
strcpy(eventna me, "MDCX_RSP") ;
and
sprintf(eventn ame, "MDCX_RSP") ;
Were you expecting any?
The contents of eventname (if an array) or the contents of the memory
it points to (if a pointer) will be the same for either statement in
this example. This would not be true if the second argument contained
anything sprintf would consider a conversion specification.
strcpy returns a pointer while sprintf returns an int but, since
either will be discarded, I don't think this is a relevant difference.
I would expect strcpy to be significantly faster but this is my
intuitive judgement and not part of the standard.
The only real difference I can see is that you need to include a
different header file depending on which you use.
<<Remove the del for email>>
On Thu, 27 Nov 2003, ios wrote:
[Incidentally, there's no need to tag your question with [Q];
that *is* the default around here, despite recent tendencies.
The only recognized subject-line tag I can think of for c.l.c
is [OT], marking off-topic posts.]
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
In this case, absolutely nothing. In general, though,
sprintf() has the whole 'format specifiers' baggage, like
printf() does; and of course sprintf() returns a character
count where strcpy() returns a pointer to the destination
array.
Note particularly that while
strcpy(d,s);
and
sprintf(d,"%s", s);
are exactly identical under all circumstances,
strcpy(d,s);
and
sprintf(d,s);
are NOT identical; consider the case where
(0 == strcmp(s,"%%")) .
HTH,
-Arthur
ios wrote:
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
I believe that strcpy will copy the final '\0', and sprintf will
not. Thus you almost certainly want to capture the return value
of sprintf.
--
Chuck F (cb********@yah oo.com) (cb********@wor ldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home .att.net> USE worldnet address!
"CBFalconer " <cb********@yah oo.com> wrote: ios wrote: strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
I believe that strcpy will copy the final '\0', and sprintf
will not. Thus you almost certainly want to capture the
return value of sprintf.
sprintf will write a '\0' to terminate the output string.
There is no difference between the two given statements,
assuming that both <stdio.h> and <string.h> are #included.
--
Simon.
Simon Biber wrote: "CBFalconer " <cb********@yah oo.com> wrote: ios wrote: > strcpy(eventnam e, "MDCX_RSP") ;
> and
> sprintf(eventna me, "MDCX_RSP") ;
I believe that strcpy will copy the final '\0', and sprintf
will not. Thus you almost certainly want to capture the
return value of sprintf.
sprintf will write a '\0' to terminate the output string.
There is no difference between the two given statements,
assuming that both <stdio.h> and <string.h> are #included.
You are correct (and I think Chuck was just hallucinating or something), but
it bears repeating (assuming someone already pointed it out) that the
strcpy version is likely to have superior performance, and that the sprintf
could break if a different string literal is used. For example,
sprintf(eventna me, "%saved"); /* !!! */
--
Richard Heathfield : bi****@eton.pow ernet.co.uk
"Usenet is a strange place." - Dennis M Ritchie, 29 July 1999.
C FAQ: http://www.eskimo.com/~scs/C-faq/top.html
K&R answers, C books, etc: http://users.powernet.co.uk/eton
In article <3F************ ***@yahoo.com>,
CBFalconer <cb********@yah oo.com> wrote: ios wrote:
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
I believe that strcpy will copy the final '\0', and sprintf will
not. Thus you almost certainly want to capture the return value
of sprintf.
They both will copy the final '\0'. The difference is what happens when
a maintenance programmer has a reason to change "MDCX_RSP" to something
else, for example something that contains % characters, and doesn't
notice that sprintf has been used...
So the second form is a bug waiting to come out and byte you where it
hurts. (The exception would be if this is within a series of sprintf
statements, where some don't have any additional arguments except the
formatting string).
there is no difference between the two cases. However if you want to
include some integer in between you can't use strcpy io****@yahoo.co m (ios) wrote in message news:<79******* *************** ***@posting.goo gle.com>... Hi
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
Thanks,
Leon
ios <io****@yahoo.c om> wrote: Hi
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
No difference.
--
== Eric Gorr ========= http://www.ericgorr.net ========= ICQ:9293199 ===
"Therefore the considerations of the intelligent always include both
benefit and harm." - Sun Tzu
== Insults, like violence, are the last refuge of the incompetent... ===
In <3F************ ***@yahoo.com> CBFalconer <cb********@yah oo.com> writes: ios wrote:
Can someone tell me what is different between below case?
strcpy(eventnam e, "MDCX_RSP") ;
and
sprintf(eventna me, "MDCX_RSP") ;
I believe that strcpy will copy the final '\0', and sprintf will
not. Thus you almost certainly want to capture the return value
of sprintf.
Don't be idiot! What do you think the 's' in sprintf stands for?
2 The sprintf function is equivalent to fprintf, except that the
output is written into an array (specified by the argument s)
rather than to a stream. A null character is written at the end
of the characters written; it is not counted as part of the
returned value.
Dan
--
Dan Pop
DESY Zeuthen, RZ group
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