handle errors when reading file

Author: RaihanSharif

implement-shell-tools/cat/cat.py

@@ -1,4 +1,5 @@
 import argparse
+import sys
 
 parser = argparse.ArgumentParser(
     prog="a simple cat implementation",
@@ -11,4 +12,25 @@
 
 args = parser.parse_args();
 
-print(args)
+# cat returns different error messages depending on the reason the path could be read
+def cat_file(path):
+    try:
+        with open(path, "r",) as f:
+            content = f.read()
+    except FileNotFoundError:
+        print(f"cat: {path}: No such file or directory", file=sys.stderr)
+        return
+    except IsADirectoryError:
+        print(f"cat: {path}: Is a directory", file=sys.stderr)
+        return
+    except PermissionError:
+        print(f"cat: {path}: Permission denied", file=sys.stderr)
+        return
+
+    print(content)
+
+
+
+for path in args.paths:
+    line_num = 1
+    cat_file(path)