path: root/lib/ic/doc/src/CORBA_Environment_alloc.xml

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  <header>
    <copyright>
      <year>1998</year><year>2009</year>
      <holder>Ericsson AB. All Rights Reserved.</holder>
    </copyright>
    <legalnotice>
      The contents of this file are subject to the Erlang Public License,
      Version 1.1, (the "License"); you may not use this file except in
      compliance with the License. You should have received a copy of the
      Erlang Public License along with this software. If not, it can be
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      basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
      the License for the specific language governing rights and limitations
      under the License.
    
    </legalnotice>

    <title>CORBA_Environment_alloc</title>
    <prepared></prepared>
    <docno></docno>
    <checked></checked>
    <date>1998-12-01</date>
    <rev>A</rev>
  </header>
  <lib>CORBA_Environment_alloc</lib>
  <libsummary>Allocation function for the CORBA_Environement struct</libsummary>
  <description>
    <p>The <em>CORBA_Environment_alloc()</em> function is the 
      function used to allocate and initiate the <em>CORBA_Environment</em>
      structure.</p>
  </description>
  <funcs>
    <func>
      <name><ret>CORBA_Environment *</ret><nametext>CORBA_Environment_alloc(inbufsz, outbufsz)</nametext></name>
      <fsummary>Initialize communication</fsummary>
      <type>
        <v>int inbufsz;</v>
        <v>int outbufsz;</v>
      </type>
      <desc>
        <p>This function is used to create and initiate the <c>CORBA_Environment</c>
          structure. In particular, it is used to dynamically allocate a CORBA_Environment
          structure and set the default values for the structure's fields. </p>
        <p><em>inbufsize</em> is the wished size of input buffer.</p>
        <p><em>outbufsize</em> is the wished size of output buffer.</p>
        <p><em>CORBA_Environment</em> is the CORBA 2.0 state structure used by the 
          generated stub.</p>
        <p>This function will set all needed default values and allocate buffers equal
          to the values passed, but will not allocate space for the _to_pid and _from_pid fields.</p>
        <p>To free the space allocated by CORBA_Environment_alloc/2 :</p>
        <list type="bulleted">
          <item>
            <p>First call CORBA_free for the input and output buffers.</p>
          </item>
          <item>
            <p>After freeing the buffer space, call CORBA_free for the CORBA_Environment space. </p>
          </item>
        </list>
      </desc>
    </func>
  </funcs>

  <section>
    <title>The CORBA_Environment structure</title>
    <p>Here is the complete definition of the CORBA_Environment structure,
      defined in file <em>ic.h</em> : </p>
    <code type="none">
/* Environment definition */
typedef struct {

  /*----- CORBA compatibility part ------------------------*/
  /* Exception tag, initially set to CORBA_NO_EXCEPTION ---*/
  CORBA_exception_type   _major;          

  /*----- External Implementation part - initiated by the user ---*/
  /* File descriptor                                              */
  int                    _fd;             
  /* Size of input buffer                                         */
  int                    _inbufsz;        
  /* Pointer to always dynamically allocated buffer for input     */
  char                  *_inbuf;         
  /* Size of output buffer                                        */
  int                    _outbufsz;       
  /* Pointer to always dynamically allocated buffer for output    */ 
  char                  *_outbuf;        
 /* Size of memory chunks in bytes, used for increasing the output
    buffer, set to >= 32, should be around >= 1024 for performance
    reasons                                                       */ 
 int                    _memchunk;       
 /* Pointer for registered name                                   */
  char                   _regname[256];   
 /* Process identity for caller                                   */
  erlang_pid            *_to_pid;         
  /* Process identity for callee                                  */ 
  erlang_pid            *_from_pid;      

  /*- Internal Implementation part - used by the server/client ---*/
  /* Index for input buffer                                       */
  int                    _iin;            
  /* Index for output buffer                                      */
  int                    _iout;          
  /* Pointer for operation name                                   */
  char                   _operation[256];
   /* Used to count parameters                                    */
  int                    _received;      
  /* Used to identify the caller                                  */
  erlang_pid             _caller;        
 /* Used to identify the call                                     */
  erlang_ref             _unique;         
  /* Exception id field                                           */
  CORBA_char            *_exc_id;        
  /* Exception value field                                        */
   void                  *_exc_value;           

  
} CORBA_Environment; 
    </code>
    <note>
      <p>Remember to set the field values <em>_fd </em>, <em>_regname </em>, <em>*_to_pid </em> and/or 
        <em>*_from_pid </em> to the appropriate application values. These are not automatically 
        set by the stubs.</p>
    </note>
    <warning>
      <p>Never assign static buffers to the buffer pointers, never set the <em>_memchunk</em> field to 
        a value less than <em>32</em>.</p>
    </warning>
  </section>

  <section>
    <title>SEE ALSO</title>
    <p>ic(3)</p>
  </section>
  
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