Change from SWIG to ctypes... much easier

[yaffs2.git] / direct / python / README.txt

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+Using python with yaffsfs
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Herewith a brief session showing yaffs direct being accessed from python.
+
+I tried SWIG first, but ctypes turned out to be way, way easier...
+
+Thanks to the people on NZPUG mailing list that helped with the exercise.
+
+Build libyaffsfs.so with the accompanying Makefile.
+
+$ make libyaffsfs.so
+
+$ python
+Python 2.6.2 (release26-maint, Apr 19 2009, 01:56:41) 
+[GCC 4.3.3] on linux2
+Type "help", "copyright", "credits" or "license" for more information.
+>>> from ctypes import *
+>>> cdll.LoadLibrary("./libyaffsfs.so")
+<CDLL './libyaffsfs.so', handle 9ed4178 at b7d418ac>
+>>> y = CDLL("./libyaffsfs.so")
+>>> y.yaffs_StartUp()
+0
+>>> y.yaffs_mount("/yaffs2")
+yaffs: Mounting /yaffs2
+yaffs: yaffs_GutsInitialise()
+yaffs_ScanBackwards starts  intstartblk 1 intendblk 256...
+0 blocks to be sorted...
+...done
+yaffs_ScanBackwards ends
+
+Block summary
+0 blocks have illegal states
+Unknown 0 blocks
+Needs scanning 0 blocks
+Scanning 0 blocks
+Empty 256 blocks
+Allocating 0 blocks
+Full 0 blocks
+Dirty 0 blocks
+Checkpoint 0 blocks
+Collecting 0 blocks
+Dead 0 blocks
+
+yaffs: yaffs_GutsInitialise() done.
+
+0
+>>> y.yaffs_open("/yaffs2/xx",66,0666)
+yaffs: Tnodes added
+Allocated block 1, seq  4097, 255 left
+0
+>>> y.yaffs_write(0,"abc",3)
+3
+>>> y.yaffs_lseek(0,0,0)
+0
+>>> b = create_string_buffer("",100)
+>>> y.yaffs_read(0,b,100)
+3
+>>> b.value
+'abc'
+>>> 
+