Module Unix

this_process_became_child_of_init returns a deferred that becomes determined when the current process becomes a child of init(8). This is useful to determine if one's parent has died, because in that case init will becomes one's parent.

See Linux_ext.pr_set_pdeathsig : Signal.t -> unit for related way to get information about parent death.

cores () Returns the number of cores

with_file file ~mode ~perm ~f ?exclusive opens file, and applies f to the resulting file descriptor. When the result of f becomes determined, it closes the descriptor and returns the result of f. If exclusive is supplied, then the file descriptor is locked before calling f and unlocked after calling f.

fcntl_getfl and fcntl_setf are deferred wrappers around the corresponding functions in Core.Unix for accessing the open-file-descriptor table.

close fd closes the file descriptor fd, and raises an exception if fd has already been closed.

In some situations, one may need to cause Async to release an fd that it is managing without closing the underlying file descriptor. In that case, one should supply ~should_close_file_descriptor:false, which will skip the underlying close() system call.

lockf fd read_or_write ?len exclusively locks for reading/writing the section of the open file fd specified by the current file position and len (see man lockf). It returns when the lock has been acquired. It raises if fd is closed.

try_lockf fd read_or_write ?len attempts to exclusively lock for reading/writing the section of the open file fd specified by the current file position and len (see man lockf). It returns true if it acquired the lock. It raises if fd is closed.

lockf_is_locked fd ?len checks the lock on section of the open file fd specified by the current file position and len (see man lockf). If the section is unlocked or locked by this process, it returns true, else it returns false. It raises if fd is closed.

unlockf fd ?len unlocks the section of the open file fd specified by the current file position and len (see man lockf). It raises if fd is closed.

The info supplied to pipe is debugging information that will be included in the returned Fds.

Create a named pipe with the given permissions.

mkstemp prefix creates and opens a unique temporary file with prefix, automatically appending a suffix of six random characters to make the name unique. Unlike C's mkstemp, prefix should not include six X's at the end.

fork_exec ~prog ~args ?path ?env forks and execs prog with args, and returns the child pid. If use_path = true (the default) and prog doesn't contain a slash, then fork_exec searches the PATH environment variable for prog. If env is supplied, it specifies the environment when prog is executed.

If env contains multiple bindings for the same variable, the last takes precedence. In the case of `Extend, bindings in env take precedence over the existing environment. See Unix.exec.

waitpid pid returns a deferred that becomes determined with the child's exit status, when the child process with process id pid exits. waitpid_exn is like waitpid, except the result only becomes determined if the child exits with status zero; it raises if the child terminates win any other way.

Return the login name of the user executing the process.

This returns a deferred because the username may need to be looked up in what is essentially a database elsewhere on the network (winbound user, or NIS).