检查进程是否存在

这是查看进程是否处于活动状态的传统的Unix方式-向其发送0信号（就像您对bash示例所做的一样）。

来自

kill(2)

   If  sig  is 0, then no signal is sent, but error checking is still

per‐
formed; this can be used to check for the existence of a process ID
or
process group ID.

并翻译成Go

package mainimport (    "fmt"    "log"    "os"    "strconv"    "syscall")func main() {    for _, p := range os.Args[1:] {        pid, err := strconv.ParseInt(p, 10, 64)        if err != nil { log.Fatal(err)        }        process, err := os.FindProcess(int(pid))        if err != nil { fmt.Printf("Failed to find process: %sn", err)        } else { err := process.Signal(syscall.Signal(0)) fmt.Printf("process.Signal on pid %d returned: %vn", pid, err)        }    }}

当您运行它时，您将得到此消息，表明进程123已死，进程1处于活动状态，但不属于您，进程12606处于活动状态，由您拥有。

$ ./kill 1 $$ 123process.Signal on pid 1 returned: operation not permittedprocess.Signal on pid 12606 returned: <nil>process.Signal on pid 123 returned: no such process