cat_implementation

Author: sarawone

implement-shell-tools/cat/cat.js

@@ -0,0 +1,38 @@
+import {program} from "commander";
+import {promises as fs} from "node:fs";
+import process from "node:process";
+
+program 
+.name ("cat")
+.description ("A JS clone for unix command cat")
+.argument("<files...>","One or more files to reach and print")
+.option("-n", "number all output lines")
+.action(async (files,options)=> {
+  for (const filePath of files){
+    try {
+        const content = await fs.readFile(filePath,"utf8");
+        if (options.n)
+        {
+            const lines = content.trimEnd().split("\n");
+            lines.forEach((line,index) => {
+            console.log(`${index+1} \t ${line}`);
+            });
+        }
+        else 
+        {
+            process.stdout.write(content);
+        }
+
+
+    }
+    catch(error)
+    {
+        console.error("No such file or directory");
+        process.exit(1);
+    }
+
+  }  
+
+});
+
+program.parse(process.argv);

implement-shell-tools/cat/package-lock.json

@@ -0,0 +1,6 @@
+{
+  "type":"module" ,
+  "dependencies": {
+    "commander": "^15.0.0"
+  }
+}