New System Calls For Reliable Multithreaded Programming

In the Oracle Solaris 11 release, the following new APIs and flags have been added to make multithreaded programs more reliable:

*at() functions – Consists of versions of file handling system calls which take the working directory for relative pathnames as an argument, to avoid races with chdir(2) calls between multiple threads.

• openat(2)

• fchownat(2)

• fstatat(2)

• utimensat(2)

• unlinkat(2)

• faccessat(2)

• fchmodat(2)

• linkat(2)

• mkdirat(2)

• mknodat(2)

• readlinkat(2)

• renameat(2)

• symlinkat(2)

Flags – The following flags close a race condition between the open(2), dup(2), and dup2(2) calls and a following call to fcntl(2) function to set the FD_CLOEXEC flag by setting it atomically in the creation system call.

• O_CLOEXEC flag to open(2)

• F_DUPFD_CLOEXEC() and F_DUP2FD_CLOEXEC() arguments to fcntl(2)