xpaconvert(7)

🎀 xpaconvert — the glow-up guide 🎀

okay bestie, so this is xpaconvert(7) from the SAORD Documentation collection, and it's literally the "how do I make my old xpa code cute again" doc. sit down, grab a strawberry, we're doing a migration ✨

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💖 NAME 💖

XPAConvert — converting the XPA API to 2.0, aka the makeover episode 🌸

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✨ SYNOPSIS ✨

This document describes tips for converting from xpa 1.0 (Xt-based xpa) to xpa 2.0 (socket-based xpa). it's giving "old era → new era" 💅

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🦋 DESCRIPTION 🦋

The following are tips for converting from xpa 1.0 (Xt-based xpa) to xpa 2.0 (socket-based xpa). The changes are straight-forward and almost can be done automatically (we used editor macros for most of the conversion). no cap, it's lowkey a find-and-replace slay 🔥

• The existence of the cpp XPA_VERSION directive to distinguish between 1.0 (where it is not defined) and 2.0 (where it is defined). 🧚
• Remove the first widget argument from all send and receive server callbacks. Also change first 2 arguments from XtPointer to void *. For example:

#ifdef XPA_VERSION
static void XPAReceiveFile(client_data, call_data, paramlist, buf, len)
     void *client_data;
     void *call_data;
     char *paramlist;
     char *buf;
     int len;
#else
static void XPAReceiveFile(w, client_data, call_data, paramlist, buf, len)
     Widget w;
     XtPointer client_data;
     XtPointer call_data;
     char *paramlist;
     char *buf;
     int len;
#endif

• Server callbacks should be declared as returning int instead of void. They now should return 0 for no errors, -1 for error. yes bestie, we report back now 💀
• The mode flags have changed when defining XPA server callbacks. The old S flag (save buffer) is replaced by freebuf=false. The old E flag (empty buffer is OK) is no longer used (it was an artifact of the X implementation). rip E flag, you will not be missed 🙈
• Change NewXPACommand() to XPAcmdNew(), with the new calling sequence:

xpa = NewXPACommand(toplevel, NULL, prefix, NULL);

is changed to:

xpa = XPACmdNew(xclass, name);

• Change the AddXPACommand() subroutine name to XPACmdAdd (with the same calling sequence):

AddXPACommand(xpa, "file",
  "\tdisplay a new file\n\t\t  requires: filename",
  NULL, NULL, NULL, XPAReceiveFile, text, NULL);

is changed to:

XPACmdAdd(xpa, "file",
  "\tdisplay a new file\n\t\t  requires: filename",
  NULL, NULL, NULL, XPAReceiveFile, text, NULL);

• The XPAXtAppInput() routine should be called just before XtAppMainLoop() to add xpa fds to the Xt event loop:

/* add the xpas to the Xt loop */
XPAXtAddInput(app, NULL);

/* process events */
XtAppMainLoop(app);

• Change NewXPA() to XPANew() and call XPAXtAddInput() if the XtAppMainLoop routine already has been entered:

xpa = NewXPA(saotng->xim->toplevel, prefix, xparoot,
             "FITS data or image filename\n\t\t  options: file type",
             XPASendData, new, NULL,
             XPAReceiveData, new, "SE");

is changed to:

sprintf(tbuf, "%s.%s", prefix, xparoot);
xpa = XPANew("SAOTNG", tbuf,
             "FITS data or image filename\n\t\t  options: file type",
             XPASendData, new, NULL,
             XPAReceiveData, new, "SE");
XPAXtAddInput(XtWidgetToApplicationContext(saotng->xim->toplevel), xpa);

• Change XPAInternalReceiveCommand() to XPACmdInternalReceive() remove first argument in the calling sequence):

XPAInternalReceiveCommand(im->saotng->xim->toplevel,
                          im->saotng, im->saotng->commands,
                          "zoom reset", NULL, 0);

is changed to:

XPACmdInternalReceive(im->saotng, im->saotng->commands,
                      "zoom reset", NULL, 0);

• Change DestroyXPA to XPAFree:

DestroyXPA(im->dataxpa);

is changed to:

XPAFree(im->dataxpa);

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👑 SEE ALSO 👑

See xpa(n) for a list of XPA help pages 🫶

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and that's the whole migration, bestie — you ate, no crumbs, periodt 💅

this little love letter is version 2.1.15, dated July 23, 2013, brought to you by the SAORD Documentation girlies. go forth and convert, main character 🌈⭐