github.com/u-root/u-root@v7.0.1-0.20200915234505-ad7babab0a8e+incompatible/cmds/core/elvish/sys/waitforread_unix.go (about)

     1  // +build !windows,!plan9
     2  
     3  package sys
     4  
     5  import "os"
     6  
     7  // WaitForRead blocks until any of the given files is ready to be read. It
     8  // returns a boolean array indicating which files are ready to be read and
     9  // possible errors.
    10  //
    11  // It is implemented with select(2) on Unix and WaitForMultipleObjects on
    12  // Windows.
    13  func WaitForRead(files ...*os.File) (ready []bool, err error) {
    14  	maxfd := 0
    15  	fdset := NewFdSet()
    16  	for _, file := range files {
    17  		fd := int(file.Fd())
    18  		if maxfd < fd {
    19  			maxfd = fd
    20  		}
    21  		fdset.Set(fd)
    22  	}
    23  	err = Select(maxfd+1, fdset, nil, nil)
    24  	ready = make([]bool, len(files))
    25  	for i, file := range files {
    26  		ready[i] = fdset.IsSet(int(file.Fd()))
    27  	}
    28  	return ready, err
    29  }