This document serves as an overview of HelenOS standard user space API implemented in HelenOS C library and the relation of this API to common standards such as "C Standard Library" (as defined by various ISO C standards, such as C99) and C POSIX Library standards.

General note: The primary aim of HelenOS C library is not a to be 100% compatible with the standards. For both many fundamental reasons (HelenOS is not an unix-like operating system) and practical reasons (our subjective dislike of some aspects of the standards, security issues, etc.) the HelenOS C library follows the standards very loosely. Many functions are not implemented because lack of current need or simple because lack of manpower and many functions closely resemble their standard-compliant counterparts, but behave very slightly differently.

unistd.h

Function

chdir

close

dup2

exit

fsync

ftruncate

getcwd

lseek

read

rmdir

sleep

unlink

usleep

write