px_delete_record(3) [debian man page]

PX_DELETE_RECORD(3)					     Library Functions Manual					       PX_DELETE_RECORD(3)

NAME

       PX_delete_record -- Removes a record from a Paradox file

SYNOPSIS

       #include <paradox.h>

       int PX_delete_record(pxdoc_t *pxdoc, int recpos)

DESCRIPTION

       Removes	the record with number recpos from the Paradox file. The first record has number 0. The data of the record will be wiped out, mak-
       ing it impossible to reconstruct it later.  The data block where the record was stored is reconstruct to make sure all records are  at  the
       beginning of the data block followed by the free space.

       Calls of PX_insert_record(3) will use the first datablock with free space and add the new record after the records in the data block.

RETURN VALUE

       Returns 0 on success or -1 on failure.

SEE ALSO

       PX_retrieve_record(3), PX_insert_record(3), PX_update_record(3)

AUTHOR

       This manual page was written by Uwe Steinmann uwe@steinmann.cx.

															       PX_DELETE_RECORD(3)

PX_GET_RECORD2(3)					     Library Functions Manual						 PX_GET_RECORD2(3)

NAME

       PX_get_record2 -- Returns record in Paradox file

SYNOPSIS

       #include <paradox.h>

       int PX_get_record2(pxdoc_t *pxdoc, int recno, char *data, int *deleted, pxdatablockinfo_t *pxdbinfo)

DESCRIPTION

       This  function is similar to PX_get_record(3) but takes two extra parameters. If *deleted is set to 1 the function will consider any record
       in the database, even those which are deleted. If *pxdbinfo is not NULL, the function will return some information  about  the  data  block
       where the record has been read from. You will have to allocate memory for pxdbinfo before calling PX_get_record2.

       On return *deleted will be set to 1 if the requested record is deleted or 0 if it is not deleted. The struct pxdatablockinfo_t has the fol-
       lowing fields:

       blockpos (long)
		 File positon where the block starts. The first six bytes of the block contain the header, followed by the record data.

       recordpos (long)
		 File position where the requested record starts.

       size (int)
		 Size of the data block without the six bytes for the header.

       recno (int)
		 Record number within the data block. The first record in the block has number 0.

       numrecords (int)
		 The number of records in this block.

       number (int)
		 The number of the data block.

       This function may return records with invalid data, because records are not explizitly marked as deleted, but rather the size  of  a  valid
       data  block  is	modified. A data block is a fixed size area in the file which holds a certain number of records. If for some reason a data
       block has newer been completely filled with records, the algorithmn anticipates deleted records in this data block, which  are  not  there.
       This often happens with the last data block in a file, which is likely to not being fully filled with records.

       If you accessing several records, do it in ascending order, because this is the most efficient way.

	      Note:

	      This function is deprecated.  Use PX_retrieve_record(3) instead

RETURN VALUE

       Returns 0 on success and -1 on failure.

SEE ALSO

       PX_get_field(3), PX_get_record(3)

AUTHOR

       This manual page was written by Uwe Steinmann uwe@steinmann.cx.

																 PX_GET_RECORD2(3)