Creates a new child process by doing one of the following in that process:
Passing string command_line
to the shell.
Invoking the executable at exe_path
.
This method has potential security vulnerabilities if called with untrusted input; see Command Injection.
Returns the process ID (pid) of the new process, without waiting for it to complete.
To avoid zombie processes, the parent process should call either:
Process.wait
, to collect the termination statuses of its children.
Process.detach
, to register disinterest in their status.
The new process is created using the exec system call; it may inherit some of its environment from the calling program (possibly including open file descriptors).
Argument env
, if given, is a hash that affects ENV
for the new process; see Execution Environment.
Argument options
is a hash of options for the new process; see Execution Options.
The first required argument is one of the following:
command_line
if it is a string, and if it begins with a shell reserved word or special built-in, or if it contains one or more meta characters.
exe_path
otherwise.
Argument command_line
String argument command_line
is a command line to be passed to a shell; it must begin with a shell reserved word, begin with a special built-in, or contain meta characters:
spawn('if true; then echo "Foo"; fi') # => 798847 # Shell reserved word. Process.wait # => 798847 spawn('exit') # => 798848 # Built-in. Process.wait # => 798848 spawn('date > /tmp/date.tmp') # => 798879 # Contains meta character. Process.wait # => 798849 spawn('date > /nop/date.tmp') # => 798882 # Issues error message. Process.wait # => 798882
The command line may also contain arguments and options for the command:
spawn('echo "Foo"') # => 799031 Process.wait # => 799031
Output:
Foo
See Execution Shell for details about the shell.
Raises an exception if the new process could not execute.
Argument exe_path
Argument exe_path
is one of the following:
The string path to an executable to be called.
A 2-element array containing the path to an executable to be called, and the string to be used as the name of the executing process.
spawn('/usr/bin/date') # Path to date on Unix-style system. Process.wait
Output:
Mon Aug 28 11:43:10 AM CDT 2023
Ruby invokes the executable directly. This form does not use the shell; see Arguments args for caveats.
If one or more args
is given, each is an argument or option to be passed to the executable:
spawn('echo', 'C*') # => 799392 Process.wait # => 799392 spawn('echo', 'hello', 'world') # => 799393 Process.wait # => 799393
Output:
C* hello world
Raises an exception if the new process could not execute.
Returns a Process::Tms
structure that contains user and system CPU times for the current process, and for its children processes:
Process.times # => #<struct Process::Tms utime=55.122118, stime=35.533068, cutime=0.0, cstime=0.002846>
The precision is platform-defined.
def foo((bar, baz)); end
^^^^^^^^^^
Foo::Bar = 1 ^^^^^^^^^^^^
Foo::Foo, Bar::Bar = 1 ^^^^^^^^ ^^^^^^^^
Foo::Bar, = baz ^^^^^^^^
def foo(**bar); end
^^^^^
def foo(**); end
^^
def foo(bar: baz); end
^^^^^^^^
def foo(bar: baz); end
^^^^^^^^
Compile a AliasMethodNode
node
Compile a ArrayPatternNode
node
Compile a CapturePatternNode
node
Compile a FindPatternNode
node
Compile a HashPatternNode
node
Compile a MatchPredicateNode
node
Save the binary_operator_loc
location using the given saved source so that it can be retrieved later.
Save the binary_operator_loc
location using the given saved source so that it can be retrieved later.