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Re: Trying to figure out how to dynamically re-allocate strings while concatenating

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Stefan Ram wrote:
> 
> Shriramana Sharma <jamadagni@gmail.com> writes:
> >Can anyone kindly point me to what I am doing wrong with realloc?
> 
>   The result of an attempt should always be checked according
>   to me. The »free« below is not really required for this
>   small program, but would be helpful in many cases, where the
>   code is repeatedly executed in a program.
> 
> #include <stdio.h>
> #include <stdlib.h>
> #include <string.h>
> 
> char * strapp( char * * const a, char const * const b )
> { *a = realloc( *a, 1 + strlen( *a )+ strlen( b ));
>   if( *a )strcat( *a, b );
>   return *a; }
> 
> int main( void )
> { char const * const name_ = "my name is";
>   char * name = malloc( strlen( name_ )+ 1 );
>   if( name )
>   { strcpy( name, name_ );
>     if( strapp( &name, " this or " ))
>     if( strapp( &name, "that." ))
>     printf( "%s\n", name );
>     free( name ); }}

I see from your call to the free function,
that you intend to free the allocated memory within main.

If either call to strapp returns a null pointer,
then your call to free, will free a null pointer instead.

-- 
pete

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Trying to figure out how to dynamically re-allocate strings while concatenating Shriramana Sharma <jamadagni@gmail.com> - 2012-08-04 07:12 -0700
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating Xavier Roche <xroche@free.fr.NOSPAM.invalid> - 2012-08-04 16:17 +0200
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating Xavier Roche <xroche@free.fr.NOSPAM.invalid> - 2012-08-04 16:22 +0200
    Re: Trying to figure out how to dynamically re-allocate strings while concatenating Shriramana Sharma <jamadagni@gmail.com> - 2012-08-04 07:25 -0700
      Re: Trying to figure out how to dynamically re-allocate strings while concatenating Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-04 16:04 +0100
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating "Heinrich Wolf" <invalid@invalid.invalid> - 2012-08-04 16:29 +0200
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-04 10:52 -0400
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating pete <pfiland@mindspring.com> - 2012-08-04 12:27 -0400
    Re: Trying to figure out how to dynamically re-allocate strings while concatenating Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-04 13:56 -0400
      Re: Trying to figure out how to dynamically re-allocate strings while  concatenating pete <pfiland@mindspring.com> - 2012-08-04 17:12 -0400
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating pete <pfiland@mindspring.com> - 2012-08-04 12:42 -0400
    Re: Trying to figure out how to dynamically re-allocate strings while concatenating Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-04 14:00 -0400
    Re: Trying to figure out how to dynamically re-allocate strings while concatenating Keith Thompson <kst-u@mib.org> - 2012-08-04 17:00 -0700
      Re: Trying to figure out how to dynamically re-allocate strings while concatenating pete <pfiland@mindspring.com> - 2012-08-04 20:48 -0400
      Re: Trying to figure out how to dynamically re-allocate strings while concatenating Jens Gustedt <jens.gustedt@loria.fr> - 2012-08-05 09:22 +0200
        Re: Trying to figure out how to dynamically re-allocate strings while concatenating Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-05 12:49 +0100
          Re: Trying to figure out how to dynamically re-allocate strings while concatenating Jens Gustedt <jens.gustedt@loria.fr> - 2012-08-05 17:12 +0200
          Re: Trying to figure out how to dynamically re-allocate strings while concatenating Keith Thompson <kst-u@mib.org> - 2012-08-05 13:17 -0700
            Re: Trying to figure out how to dynamically re-allocate strings while concatenating Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-05 22:53 +0100
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating Shriramana Sharma <jamadagni@gmail.com> - 2012-08-04 19:20 -0700
  Re: C Vs Asm i use for cat function "io_x" <a@b.c.invalid> - 2012-08-05 08:15 +0200
    Re: C Vs Asm i use for cat function "BartC" <bc@freeuk.com> - 2012-08-05 10:22 +0100
      Re: C Vs Asm i use for cat function "Heinrich Wolf" <invalid@invalid.invalid> - 2012-08-05 17:00 +0200
        Re: C Vs Asm i use for cat function Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-05 16:20 +0100
      Re: C Vs Asm i use for cat function "io_x" <a@b.c.invalid> - 2012-08-05 19:51 +0200
        Re: C Vs Asm i use for cat function "BartC" <bc@freeuk.com> - 2012-08-05 21:04 +0100
  Re: Trying to figure out how to dynamically re-allocate strings while concatenating Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-08-10 10:45 +0300

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