Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>Here's an example of what we were discussing. This code expects the caller to allocate the buffer.</p> <h3>Test code (Windows)</h3> <pre><code>// IN: test=pre-allocated buffer. // IN: size=size of pre-allocated buffer. // RETURNS: 0 and size set to required size. // 1 and size set to size used. __declspec(dllexport) int testout(void *pdata, int *psize) { unsigned char * p = (unsigned char *)pdata; if (*psize &lt; 5) { *psize = 5; // set size required return 0; // fail } p[0] = 123; p[1] = 255; p[2] = 237; p[3] = 12; p[4] = 222; *psize = 5; // indicate size used return 1; // pass } </code></pre> <h3>Python</h3> <pre><code>from ctypes import * test = CDLL('test') size = c_int(0) test.testout.argtypes=[c_void_p,POINTER(c_int)] print "Result of NULL pointer and zero size:",test.testout(None,byref(size)) print "Returned size:",size.value mem = (c_ubyte * 2)() size = c_int(sizeof(mem)) print "sizeof(mem):",size.value print "Result of small buffer:",test.testout(byref(mem),byref(size)) print "Returned size:",size.value mem = (c_ubyte * size.value)() print "Result of exact size buffer:",test.testout(byref(mem),byref(size)) print "Returned size:",size.value for i in range(size.value): print mem[i] mem = (c_ubyte * 20)() size = c_int(20) print "Result of bigger buffer:",test.testout(byref(mem),byref(size)) print "Returned size:",size.value for i in range(size.value): print mem[i] </code></pre> <h3>Output</h3> <pre><code>Result of NULL pointer and zero size: 0 Returned size: 5 sizeof(mem): 2 Result of small buffer: 0 Returned size: 5 Result of exact size buffer: 1 Returned size: 5 123 255 237 12 222 Result of bigger buffer: 1 Returned size: 5 123 255 237 12 222 </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POPython and C interop: Dynamic resizing of ctypes
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USMark Tolonen
    1. USMark Tolonen
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POPython and C interop: Dynamic resizing of ctypes
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COGreat, thank you very much for your help Mark
      singulars
      1. PO
      1. USCharlieY
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload