From 712a9fd9721c314f4b0238577d803b012845f6d2 Mon Sep 17 00:00:00 2001
From: "W. Felix Handte" <w@felixhandte.com>
Date: Fri, 29 Jun 2018 15:33:44 -0400
Subject: [PATCH] Allow Invoking `zstd --list` When `stdin` is not a `tty`

Also now returns an error when no inputs are given.

New proposed behavior:

```
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l; echo $?
No files given
1
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l Makefile.zst; echo $?
Frames  Skips  Compressed  Uncompressed  Ratio  Check  Filename
     1      0     3.08 KB      10.92 KB  3.544  XXH64  Makefile.zst
0
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l <Makefile.zst; echo $?
zstd: --list does not support reading from standard input
No files given
1
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l Makefile.zst <Makefile.zst; echo $?
Frames  Skips  Compressed  Uncompressed  Ratio  Check  Filename
     1      0     3.08 KB      10.92 KB  3.544  XXH64  Makefile.zst
0
felix@odin:~/prog/zstd (list-stdin-check)$
```
---
 programs/fileio.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/programs/fileio.c b/programs/fileio.c
index 0175b3163..b4eed28d1 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -2017,21 +2017,25 @@ static int FIO_listFile(fileInfo_t* total, const char* inFileName, int displayLe
 }
 
 int FIO_listMultipleFiles(unsigned numFiles, const char** filenameTable, int displayLevel){
-
-    if (!IS_CONSOLE(stdin)) {
-        DISPLAYOUT("zstd: --list does not support reading from standard input\n");
-        return 1;
+    unsigned u;
+    for (u=0; u<numFiles;u++) {
+        if (!strcmp (filenameTable[u], stdinmark)) {
+            DISPLAYOUT("zstd: --list does not support reading from standard input\n");
+            return 1;
+        }
     }
 
     if (numFiles == 0) {
+        if (!IS_CONSOLE(stdin)) {
+            DISPLAYOUT("zstd: --list does not support reading from standard input\n");
+        }
         DISPLAYOUT("No files given\n");
-        return 0;
+        return 1;
     }
     if (displayLevel <= 2) {
         DISPLAYOUT("Frames  Skips  Compressed  Uncompressed  Ratio  Check  Filename\n");
     }
     {   int error = 0;
-        unsigned u;
         fileInfo_t total;
         memset(&total, 0, sizeof(total));
         total.usesCheck = 1;