StrBuf::StringInit()

Initialize a StrBuf.

Virtual?	No
Class	StrBuf
Arguments	None
Returns	void

Notes

StringInit() initializes the StrBuf to contain a zero-length null buffer.

Normally when a StrBuf is created, it is initialized using the StrBuf constructor. However, there might be specialized cases where memory has already been allocated for a StrBuf instance, but the memory was not allocated through the normal mechanisms that would result in the StrBuf constructor initializing the instance. For these specialized cases, StringInit() is appropriate for initializing a StrBuf instance.

After a StrBuf has been used, calling StringInit() for the instance can result in a memory leak. Specifically, once the buffer member has been pointed to memory other than nullStrBuf, calling StringInit() for the instance will abandon the memory.

In most cases, it is preferable to use an alternative such as one of the following:

sb1 = StrRef::Null();

sb2.Clear();
sb2.Terminate();

sb3.Set( "" );

sb4 = "";

See also

StrBuf::Clear() StrBuf::Set() StrBuf::Terminate() StrBuf::operator =( char * ) StrRef::Null()

Example

#include <iostream>
#include <errno.h>

#include <stdhdrs.h>
#include <strbuf.h>

#define NSTRBUFS     5
#define CHUNKSIZE    1024
#define STRBUFSIZE   sizeof( StrBuf )

int main( int argc, char **argv )
{
    char chunk[ CHUNKSIZE ];
    int chunkFree = CHUNKSIZE;
    char *pchunkStart = &chunk[ 0 ];
    char *pchunk;

    int iStrBuf;

    // Initialize the StrBufs in the chunk.

    for ( iStrBuf = 0, pchunk = pchunkStart;
         iStrBuf < NSTRBUFS;
         iStrBuf, pchunk += STRBUFSIZE )
    {
        // Ensure that there's enough free left in the chunk for a StrBuf.
        if ( (chunkFree -= STRBUFSIZE) &lt; 0)
        {
            cout &lt;&lt; "Not enough free left in the chunk!\n";
            return ENOMEM;
        }

        // Initialize and set the value of the StrBuf.

        ((StrBuf *)pchunk)-&gt;StringInit();
        *(StrBuf *)pchunk &lt;&lt; iStrBuf + 73;
    }

    // Print the StrBufs. Do this in a separate loop so as to provide
    // some evidence that the above loop didn't corrupt adjacent StrBufs.
    for ( iStrBuf = 0, pchunk = pchunkStart;
          iStrBuf &lt; NSTRBUFS;
          iStrBuf, pchunk += STRBUFSIZE )
    {
        cout << "StrBuf " << iStrBuf + 1 << " contains \"";
        cout << ((StrBuf *)pchunk)->Text() << "\"\n";
    }
}

Executing the preceding code produces the following output:

StrBuf 1 contains "73"
StrBuf 2 contains "74"
StrBuf 3 contains "75"
StrBuf 4 contains "76"
StrBuf 5 contains "77"