diff --git a/envar-tool.js b/envar-tool.js
index fbc483d..e6878b5 100644
--- a/envar-tool.js
+++ b/envar-tool.js
@@ -2,6 +2,8 @@ const fs = require('fs')
 const path = require('path')
 const chokidar = require('chokidar')
 const assign_deep = require('assign-deep')
+const readlineSync = require('readline-sync')
+
 //const deepmerge = require('deepmerge')
 // https://github.com/jonschlinkert/assign-deep // 类似 Object.assign 直接赋值到第一个对象里。只下载2个包。assign 优选。
 // https://github.com/jonschlinkert/merge-deep // 生成一个新对象。会下载7～8个包。
@@ -30,6 +32,45 @@ module.exports = {
     })
   },
 
+  get_simsimPath ({ envarFiles = [], readable = false, readPrompt = '' }) {
+    let simsimPath
+    // 用户自己定义的优先
+    for (let configFile of envarFiles) {
+      try {
+        const envar = require(path.resolve(configFile))
+        if (envar?.simsimPath) {
+          try {
+            require(path.resolve(envar.simsimPath))
+            simsimPath = envar?.simsimPath
+          } catch (expt) {
+            console.log('!!! ' + path.resolve(envar.simsimPath) + ' is invalid!')
+          }
+        }
+      } catch (expt) {
+        console.log('bad format!', path.resolve(configFile))
+      }
+    }
+    // 其次检测是否已安装
+    if (!simsimPath) {
+      module.paths.forEach((modulesPath) => {
+        if (fs.existsSync(`${modulesPath}/sesame-basic`)) {
+          simsimPath = `${modulesPath}/sesame-basic`
+        }
+      })
+    }
+    // 最后等待用户输入
+    while (!simsimPath && readable) {
+      simsimPath = readlineSync.question(readPrompt)
+      try {
+        require(path.resolve(simsimPath))
+      } catch (expt) {
+        console.log('!!! ' + path.resolve(simsimPath) + ' is invalid!')
+        simsimPath = ''
+      }
+    }
+    return simsimPath
+  },
+
   /** 合并 envar files 和 commander parameters 中的环境变量。
    * @param envarFiles:
    *  - 字符串: 导入文件，内容应当是字符串数组，或者对象。
diff --git a/package.json b/package.json
index 2ef40a1..eed27fe 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,8 @@
   "dependencies": {
     "assign-deep": "^1.0.1",
     "chokidar": "^4.0.0",
-    "commander": "^4.1.1"
+    "commander": "^4.1.1",
+    "readline-sync": "^1.4.10"
   },
   "scripts": {
     "setup": "npm install"