From a11658737a292d0dbbbb13feb9c83f99c5773546 Mon Sep 17 00:00:00 2001
From: Peter Elliott <pelliott@ualberta.ca>
Date: Tue, 6 Jul 2021 14:14:54 -0600
Subject: [PATCH] Userland: Less: emulate cat when stdout is not a tty

This is the most logical behavior when less is used in a pipe.
---
 Userland/Utilities/less.cpp | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/Userland/Utilities/less.cpp b/Userland/Utilities/less.cpp
index 3662ba59a2..f89be6c5f4 100644
--- a/Userland/Utilities/less.cpp
+++ b/Userland/Utilities/less.cpp
@@ -286,10 +286,26 @@ static String get_key_sequence()
     return String(buff, n);
 }
 
+static void cat_file(FILE* file)
+{
+    ByteBuffer buffer = ByteBuffer::create_uninitialized(4096);
+    while (!feof(file)) {
+        size_t n = fread(buffer.data(), 1, buffer.size(), file);
+        if (n == 0 && ferror(file)) {
+            perror("fread");
+            exit(1);
+        }
+
+        n = fwrite(buffer.data(), 1, n, stdout);
+        if (n == 0 && ferror(stdout)) {
+            perror("fwrite");
+            exit(1);
+        }
+    }
+}
+
 int main(int argc, char** argv)
 {
-    VERIFY(isatty(STDOUT_FILENO));
-
     char const* filename = "-";
     char const* prompt = "?f%f :.(line %l)?e (END):.";
     bool dont_switch_buffer = false;
@@ -321,6 +337,11 @@ int main(int argc, char** argv)
         prompt = "--More--";
     }
 
+    if (!isatty(STDOUT_FILENO)) {
+        cat_file(file);
+        return 0;
+    }
+
     setup_tty(!dont_switch_buffer);
 
     Pager pager(file, stdout, g_wsize.ws_col, g_wsize.ws_row);