Hi
I have a program within which i have the following statement.
sprintf(somevar ,"%s/%s.%s",PREFIX.c _str( ),MIDDLE.c_str(
),SUFFIX.c_str( ) );
Here PREFIX, MIDDLE and SUFFIX are all const strings.
This works fine but recently after close to 1000 successful runs my
program dumped with SIGSEGV.
I did a bt on the core file at gdb prompt and found that the problem is
with c_str( )
I am using gcc 3.2.3
libstdc++.so.5
on RH linux AS 3.
Is the spriontf statement correct , or is there any better way.
thanks
Shyam
12  5285 
Dnia 27 Sep 2006 02:47:52 -0700, shyam napisa³(a):
sprintf(somevar ,"%s/%s.%s",PREFIX.c _str( ),MIDDLE.c_str(
),SUFFIX.c_str( ) );
What is "somevar" ?
Is the spriontf statement correct , or is there any better way.
Did you try to use stringstream or normal string concatenation?
--
SirMike - http://www.sirmike.org
C makes it easy to shoot yourself in the foot; C++ makes it harder, but
when you do, it blows away your whole leg. - Bjarne Stroustrup
shyam wrote:
Hi
I have a program within which i have the following statement.
sprintf(somevar ,"%s/%s.%s",PREFIX.c _str( ),MIDDLE.c_str(
),SUFFIX.c_str( ) );
Here PREFIX, MIDDLE and SUFFIX are all const strings.
This works fine but recently after close to 1000 successful runs my
program dumped with SIGSEGV.
I did a bt on the core file at gdb prompt and found that the problem is
with c_str( )
I am using gcc 3.2.3
libstdc++.so.5
on RH linux AS 3.
Is the spriontf statement correct , or is there any better way.
I'd blame some of your (not shown) code that probably
overwrites some internal memory of the strings, hence
the c_str() segfault.
<OT>
If you are on a 32-bit platform, try valgrind to pinpoint
the error.
</OT>
HTH,
- J.
I havent used string or stringstream concatenation.
And i am not using these const strings in any other way.
I feel it is better to concatenate these three strings into one string
object and then so a c_str( ) on that object.
Jacek Dziedzic wrote:
shyam wrote:
Hi
I have a program within which i have the following statement.
sprintf(somevar ,"%s/%s.%s",PREFIX.c _str( ),MIDDLE.c_str(
),SUFFIX.c_str( ) );
Here PREFIX, MIDDLE and SUFFIX are all const strings.
This works fine but recently after close to 1000 successful runs my
program dumped with SIGSEGV.
I did a bt on the core file at gdb prompt and found that the problem is
with c_str( )
I am using gcc 3.2.3
libstdc++.so.5
on RH linux AS 3.
Is the spriontf statement correct , or is there any better way.
I'd blame some of your (not shown) code that probably
overwrites some internal memory of the strings, hence
the c_str() segfault.
<OT>
If you are on a 32-bit platform, try valgrind to pinpoint
the error.
</OT>
HTH,
- J.
shyam wrote:
I havent used string or stringstream concatenation.
And i am not using these const strings in any other way.
I feel it is better to concatenate these three strings into one string
object and then so a c_str( ) on that object.
Why? char* is not a #$*&@!@ string. It's a pointer to
a single character. This isn't C.
string somevar = PREFIX + '/' + MIDDLE + '.' + SUFFIX;
or
ostringstream os;
os << PREFIX << "/" << MIDDLE << "." << SUFFIX;
string somevar = os.str();
Ron Natalie wrote:
shyam wrote:
I havent used string or stringstream concatenation.
And i am not using these const strings in any other way.
I feel it is better to concatenate these three strings into one string
object and then so a c_str( ) on that object.
Why? char* is not a #$*&@!@ string. It's a pointer to
a single character. This isn't C.
You are correct but i want the final string in char * form and not C++
string
string somevar = PREFIX + '/' + MIDDLE + '.' + SUFFIX;
or
ostringstream os;
os << PREFIX << "/" << MIDDLE << "." << SUFFIX;
string somevar = os.str();
shyam wrote:
Ron Natalie wrote:
shyam wrote:
I havent used string or stringstream concatenation.
And i am not using these const strings in any other way.
>
I feel it is better to concatenate these three strings into one string
object and then so a c_str( ) on that object.
Why? char* is not a #$*&@!@ string. It's a pointer to
a single character. This isn't C.
You are correct but i want the final string in char * form and not C++
string
Well, it's your hair. You're problem could very well be a buffer
overrun. This is what happens when you use buffers...they eventually
bite you really hard.
On 27 Sep 2006 08:07:48 -0700, I waved a wand and this message
magically appears in front of shyam:
Why? char* is not a #$*&@!@ string. It's a pointer to
a single character. This isn't C.
You are correct but i want the final string in char * form and not C++
string
Use c_str() on the resulting string. Simple.
-- http://www.munted.org.uk
You've been eating the cat food again, haven't you?
Hi,
I'm not sure, but I think c_str() allocates new memory which has to be freed
by delete.
shyam wrote:
Hi
I have a program within which i have the following statement.
sprintf(somevar ,"%s/%s.%s",PREFIX.c _str( ),MIDDLE.c_str(
),SUFFIX.c_str( ) );
Here PREFIX, MIDDLE and SUFFIX are all const strings.
This works fine but recently after close to 1000 successful runs my
program dumped with SIGSEGV.
I did a bt on the core file at gdb prompt and found that the problem is
with c_str( )
I am using gcc 3.2.3
libstdc++.so.5
on RH linux AS 3.
Is the spriontf statement correct , or is there any better way.
thanks
Shyam
Thorsten Kiefer wrote:
Hi,
I'm not sure, but I think c_str() allocates new memory which has to be freed
by delete.
Not a 'delete' in user code, that's for sure.
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