TCL技术问询：外部程序多文件打开及等待加载后执行后续操作

1. Opening Multiple Files via External Programs in TCL #

There are a few straightforward ways to handle this, depending on whether you want to launch programs in parallel or sequentially:

• Launching programs in parallel (no waiting):
  On Windows, use the start command with exec to kick off programs without waiting for them to finish:

  # Open three text files with Notepad all at once
  exec start notepad "file1.txt" &
  exec start notepad "file2.txt" &
  exec start notepad "file3.txt" &
  

  On Unix-like systems (Linux/macOS), append & to the exec command to background the process:

  # Open multiple files with gedit
  exec gedit "file1.txt" &
  exec gedit "file2.txt" &
  

  If your external program supports opening multiple files in a single call (most media players do), you can pass all paths at once to avoid multiple process launches:

  # Load three videos into your player in one go
  exec /path/to/your-player "video1.mp4" "video2.mp4" "video3.mp4" &
  

2. Waiting for a Program to Fully Load Before Proceeding #

Detecting when a program is "fully loaded" is a bit nuanced—since "loaded" can mean different things (process started, window visible, ready to accept input). Here are tailored solutions for your use cases:

For Office Apps (PowerPoint/Word) #

On Windows, the TWAPI extension (a TCL library for Windows API access) lets you check if the app's window exists, which is a reliable sign it's ready. Here's a practical example:

package require twapi

# Launch PowerPoint first
exec start powerpoint "presentation.pptx" &

# Wait until PowerPoint's window is detected
set is_ready 0
while {!$is_ready} {
  # Look for windows with "PowerPoint" in the title (adjust if your title varies)
  set matching_windows [twapi::win_find -title *PowerPoint*]
  if {[llength $matching_windows] > 0} {
    set is_ready 1
  } else {
    after 500 ;# Wait 500ms before checking again to avoid spamming the system
  }
}

# Now launch your Word document
exec start winword "document.docx" &

If you don't want to use TWAPI, you could use tasklist to check if the process is running, but that only confirms the process started—not that it's fully loaded.

For Your Specific Video Player #

Since your player accepts commands via a pipe when running, here's how to handle both running and closed states:

# Adjust this to your player's actual pipe path
set pipe_path "\\\\.\\pipe\\my-player-pipe" ;# Windows named pipe
# For Linux: set pipe_path "/tmp/my-player-pipe"

# Check if the player is already running (pipe exists)
if {[file exists $pipe_path]} {
  # Send videos directly via the pipe
  set pipe_handle [open $pipe_path w]
  puts $pipe_handle "open video1.mp4"
  puts $pipe_handle "open video2.mp4"
  close $pipe_handle
} else {
  # Launch the player first
  exec /path/to/your-player &
  
  # Wait until the pipe is created (signaling the player is ready)
  set is_ready 0
  while {!$is_ready} {
    if {[file exists $pipe_path]} {
      set is_ready 1
    } else {
      after 500
    }
  }
  
  # Now send the videos to the ready player
  set pipe_handle [open $pipe_path w]
  puts $pipe_handle "open video1.mp4"
  puts $pipe_handle "open video2.mp4"
  close $pipe_handle
}

Note: You'll need to tweak the pipe path and the command format (like "open [file]") to match your player's actual pipe API.

内容的提问来源于stack exchange，提问作者Badri