github.com/cockroachdb/cockroach@v20.2.0-alpha.1+incompatible/pkg/util/sdnotify/sdnotify.go (about)

     1  // Copyright 2017 The Cockroach Authors.
     2  //
     3  // Use of this software is governed by the Business Source License
     4  // included in the file licenses/BSL.txt.
     5  //
     6  // As of the Change Date specified in that file, in accordance with
     7  // the Business Source License, use of this software will be governed
     8  // by the Apache License, Version 2.0, included in the file
     9  // licenses/APL.txt.
    10  
    11  // Package sdnotify implements both sides of the systemd readiness
    12  // protocol. Servers can use sdnotify.Ready() to signal that they are
    13  // ready to receive traffic, and process managers can use
    14  // sdnotify.Exec() to run processes that implement this protocol.
    15  package sdnotify
    16  
    17  import "os/exec"
    18  
    19  // Ready sends a readiness signal using the systemd notification
    20  // protocol. It should be called (once) by a server after it has
    21  // completed its initialization (including but not necessarily limited
    22  // to binding ports) and is ready to receive traffic.
    23  func Ready() error {
    24  	return ready()
    25  }
    26  
    27  // Exec the given command in the background using the systemd
    28  // notification protocol. This function returns once the command has
    29  // either exited or signaled that it is ready. If the command exits
    30  // with a non-zero status before signaling readiness, returns an
    31  // exec.ExitError.
    32  func Exec(cmd *exec.Cmd) error {
    33  	return bgExec(cmd)
    34  }