sd-readahead — Reference implementation of APIs for controlling boot-time read-ahead
sd-readahead.h provide a
reference implementation for APIs for controlling boot-time
read-ahead, as implemented by the read-ahead subsystem
See sd_readahead(3) for more information about the function implemented.
This interface is provided by the reference implementation of APIs for controlling boot-time read-ahead and distributed with the systemd package. The algorithms it implements are simple, and can easily be reimplemented in daemons if it is important to support this interface without using the reference implementation. See the respective function man pages for details.
In addition, for details about the algorithms, check the liberally licensed reference implementation sources: http://cgit.freedesktop.org/systemd/systemd/plain/src/readahead/sd-readahead.c and http://cgit.freedesktop.org/systemd/systemd/plain/src/systemd/sd-readahead.h
These APIs are implemented in the reference
sd-readahead.h files. It is
recommended that applications consuming these APIs copy
the implementation into their source tree, either
verbatim or in excerpts. These interfaces are
currently not available in a dynamic library.
The functions provided by this interface become
NOPs when -DDISABLE_SYSTEMD is set during
compilation. In addition, if
sd-readhead.c is compiled on
non-Linux systems it becomes NOPs.