NAME

       pmem2_source_pread_mcsafe(),  pmem2_source_pwrite_mcsafe() - read source contents or write
       to the source in a safe manner

SYNOPSIS

              #include <libpmem2.h>

              struct pmem2_source;
              int pmem2_source_pread_mcsafe(struct pmem2_source *src, void *buf, size_t size,
                      size_t offset);
              int pmem2_source_pwrite_mcsafe(struct pmem2_source *src, void *buf, size_t size,
                      size_t offset);

DESCRIPTION

       The pmem2_source_pread_mcsafe() function reads size bytes from the source src starting  at
       offset  offset into the buffer buf.  The pmem2_source_pwrite_mcsafe() function writes size
       bytes from the buffer buf to the source src starting at the offset offset.

       Above functions are capable of detecting bad blocks and handling the SIGBUS signal  thrown
       when  accessing a bad block.  When a bad block is encountered, pmem2_source_pread_mcsafe()
       and pmem2_source_pwrite_mcsafe() functions return corresponding error.  A  signal  handler
       for  SIGBUS  signal  is  registered  using  sigaction(2)  for  the  running  time of those
       operations.  This capability is limited to POSIX systems.

       For   bad   block   detection    and    clearing,    see    pmem2_badblock_context_new(3),
       pmem2_badblock_next(3) and pmem2_badblock_clear(3).

RETURN VALUE

       The  pmem2_source_pread_mcsafe()  and  pmem2_source_pwrite_mcsafe()  functions return 0 on
       success or a negative error code on failure.

ERRORS

       The  pmem2_source_pread_mcsafe()  and  pmem2_source_pwrite_mcsafe()  can  fail  with   the
       following errors:

       • PMEM2_E_IO_FAIL  -  a  physical  I/O  error  occurred during the read/write operation, a
         possible bad block encountered.

       • PMEM2_E_LENGTH_OUT_OF_RANGE - read/write operation size size  from  offset  offset  goes
         beyond the file length.

       • PMEM2_E_SOURCE_TYPE_NOT_SUPPORTED   -  read/write  operation  doesn't  support  provided
         source,     only     sources     created      with      pmem2_source_from_fd(3)      and
         pmem2_source_from_handle(3) are supported.

       Those  operations  can  also  return  all  errors from the underlying pread(2), pwrite(2),
       sigaction(2) functions on POSIX systems and ReadFile(), WriteFile() functions on Windows.

SEE ALSO

       pread(2),      pwrite(2),      ReadFile(),      WriteFile(),      pmem2_badblock_clear(3),
       pmem2_badblock_context_new(3),       pmem2_badblock_next(3),      pmem2_source_from_fd(3),
       pmem2_source_from_handle(3), libpmem2(7) and <https://pmem.io>