[#BloombergLP-bdlsb-OverflowMemOutStreamBuf-xsputn] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bdlsb.adoc[bdlsb]::xref:BloombergLP/bdlsb/OverflowMemOutStreamBuf.adoc[OverflowMemOutStreamBuf]::xsputn :relfileprefix: ../../../ :mrdocs: Write the specified `numChars` characters from the specified `source` to the stream buffer. Return the number of characters successfully written. The behavior is undefined unless '(source && 0 < numChars) || 0 == numChars'. == Synopsis Declared in `<bdlsb_overflowmemoutstreambuf.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- virtual std::streamsize xsputn( char_type const* source, std::streamsize numChars) override; ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#