11-13-2013
What if the file is held open by an application running? Will that application write to file offset 0, or will the file continue to exist on disk, but lose its directory entry?
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LEARN ABOUT OPENSOLARIS
posix_fadvise
posix_fadvise(3C) Standard C Library Functions posix_fadvise(3C)
NAME
posix_fadvise - file advisory information
SYNOPSIS
#include <fcntl.h>
int posix_fadvise(int fd, off_t offset, off_t len, int advice);
DESCRIPTION
The posix_fadvise() function advises the system on the expected behavior of the application with respect to the data in the file associated
with the open file descriptor, fd, starting at offset and continuing for len bytes. The specified range need not currently exist in the
file. If len is zero, all data following offset is specified. The system may use this information to optimize handling of the specified
data. The posix_fadvise() function has no effect on the semantics of other operations on the specified data, although it may affect the
performance of other operations.
The advice to be applied to the data is specified by the advice parameter and may be one of the following values:
POSIX_FADV_NORMAL Specifies that the application has no advice to give on its behavior with respect to the specified data. It is the
default characteristic if no advice is given for an open file.
POSIX_FADV_SEQUENTIAL Specifies that the application expects to access the specified data sequentially from lower offsets to higher off-
sets.
POSIX_FADV_RANDOM Specifies that the application expects to access the specified data in a random order.
POSIX_FADV_WILLNEED Specifies that the application expects to access the specified data in the near future.
POSIX_FADV_DONTNEED Specifies that the application expects that it will not access the specified data in the near future.
POSIX_FADV_NOREUSE Specifies that the application expects to access the specified data once and then not reuse it thereafter.
These values are defined in <fcntl.h>
RETURN VALUES
Upon successful completion, posix_fadvise() returns zero. Otherwise, an error number is returned to indicate the error.
ERRORS
The posix_fadvise() function will fail if:
EBADF The fd argument is not a valid file descriptor.
EINVAL The value of advice is invalid, or the value of len is less than zero.
ESPIPE The fd argument is associated with a pipe or FIFO.
USAGE
The posix_fadvise() function has a transitional interface for 64-bit file offsets. See lf64(5).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Committed |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
|Standard |See standards(5). |
+-----------------------------+-----------------------------+
SEE ALSO
posix_madvise(3C), attributes(5), standards(5)
SunOS 5.11 14 Jul 2008 posix_fadvise(3C)