Thanks again tye. I ended up with the following:

SV *
odbc_lob_read(sth, colno, bufsv, length, attr = NULL)
     SV  *sth
     int colno
     SV  *bufsv
     UV  length
     SV  *attr;
    PROTOTYPE: $$$$;$
    PREINIT:
     char *buf;
     UV   ret_len;
     IV   sql_type = 0;
    INIT:
     if (length == 0) {
         croak("Cannot retrieve 0 length lob");
     }
    CODE:
     if (attr) {
         SV **svp;
         DBD_ATTRIBS_CHECK("odbc_lob_read", sth, attr);
         DBD_ATTRIB_GET_IV(attr, "Type", 4, svp, sql_type);
     }
     if (SvROK(bufsv)) {
        bufsv = SvRV(bufsv);
     }
     sv_setpvn(bufsv, "", 0);                   /* ensure we can grow 
+ok */

     buf = SvGROW(bufsv, length + 1);
     ret_len = odbc_st_lob_read(sth, colno, bufsv, length, sql_type);
     if (ret_len > 0) {
         SvCUR_set(bufsv, ret_len);      /* set length in SV */
         *SvEND(bufsv) = '\0';           /* NUL terminate */
         SvSETMAGIC(bufsv);
         RETVAL = newSViv(ret_len);
     } else {
         XSRETURN_UNDEF;
     }
     OUTPUT:
        RETVAL

[download]

Thanks again for your suggestions.

In reply to Re^4: Perl XS - is this code required in DBD::Pg? (empty) by mje
in thread Perl XS - is this code required in DBD::Pg? by mje

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