SYNOPSIS

A description of the XPA client-side programming interface.

DESCRIPTION

Introduction to XPA Client Programming

Sending/receiving data to/from an XPA access point is easy: you generally only need to call the XPAGet() or XPASet() subroutines.

  #include <xpa.h>
  int XPAGet(XPA xpa,
      char *template, char *paramlist, char *mode,
      char **bufs, size_t *lens, char **names, char **messages, int n);
  int XPASet(XPA xpa,
      char *template, char *paramlist, char *mode,
      char *buf, size_t len, char **names, char **messages, int n);
  int XPAInfo(XPA xpa,
      char *template, char *paramlist, char *mode,
      char **names, char **messages, int n);
  int XPAAccess(XPA xpa,
      char *template, char *paramlist, char *mode,
      char **names, char **messages, int n);
  int XPAGetFd(XPA xpa,
      char *template, char *paramlist, char *mode,
      int *fds, char **names, char **messages, int n);
  int XPASetFd(XPA xpa,
      char *template, char *paramlist, char *mode,
      int fd, char **names, char **messages, int n);
  XPA XPAOpen(char *mode);
  void XPAClose(XPA xpa);
  int XPANSLookup(XPA xpa,
      char *template, char *type,
      char ***classes, char ***names, char ***methods, char ***infos);

Introduction

To use the XPA application programming interface, a software developer generally will include the xpa.h definitions file:

  #include <xpa.h>

in the software module that defines or accesses an XPA access point and then will link against the libxpa.a library:

  gcc -o foo foo.c libxpa.a

XPA has been compiled using both C and C++ compilers.

Client communication with XPA public access points generally is accomplished using XPAGet() or XPASet() within a program (or xpaget and xpaset at the command line). Both routines require specification of the name of the access point. If a template is used to specify the access point name (e.g., ``ds9*''), then communication will take place with all servers matching that template.