Fix some cat abuses in code, plugins

misc/clipboard-copier/copier

@@ -8,16 +8,16 @@
 SELECTION=${XDG_CONFIG_HOME:-$HOME/.config}/nnn/.selection
 
 # Linux
-cat "$SELECTION" | xargs -0 | xsel -bi
+xargs -0 < "$SELECTION" | xsel -bi
 
 # macOS
-# cat "$SELECTION" | xargs -0 | pbcopy
+# xargs -0 < "$SELECTION" | pbcopy
 
 # Termux
-# cat "$SELECTION" | xargs -0 | termux-clipboard-set
+# xargs -0 < "$SELECTION" | termux-clipboard-set
 
 # Cygwin
-# cat "$SELECTION" | xargs -0 | clip
+# xargs -0 < "$SELECTION" | clip
 
 # Wayland
-# cat "$SELECTION" | xargs -0 | wl-copy
+# xargs -0 < "$SELECTION" | wl-copy

plugins/fzhist

@@ -10,10 +10,10 @@ shellname="$(basename "$SHELL")"
 
 if [ "$shellname" = "bash" ]; then
     hist_file="$HOME/.bash_history"
-    entry="$(cat "$hist_file" | fzy)"
+    entry="$(fzy < "$hist_file")"
 elif [ "$shellname" = "fish" ]; then
     hist_file="$HOME/.config/fish/fish_history"
-    entry="$(cat "$hist_file" | grep "\- cmd: " | cut -c 8- | fzy)"
+    entry="$(grep "\- cmd: " "$hist_file" | cut -c 8- | fzy)"
 fi
 
 if ! [ -z "$entry" ]; then
@@ -21,10 +21,8 @@ if ! [ -z "$entry" ]; then
     echo "$entry" >> $tmpfile
     $EDITOR $tmpfile
 
-    cmd="$(cat $tmpfile)"
-
-    if ! [ -z "$cmd" ]; then
-        $SHELL -c "$cmd"
+    if [ -s $tmpfile ]; then
+        $SHELL -c "$(cat $tmpfile)"
     fi
 
     rm $tmpfile

plugins/ndiff

@@ -25,9 +25,9 @@ if [ -s $selection ]; then
         else
             # If xargs supports the -o option, use it to get rid of:
             #     Vim: Warning: Input is not from a terminal
-            # cat $selection | xargs -0 -o vimdiff
+            # xargs -0 -o vimdiff < $selection
 
-            cat $selection | xargs -0 vimdiff +0
+            xargs -0 vimdiff +0 < $selection
         fi
     else
         echo "needs at least 2 files or directories selected for comparison"

plugins/picker

@@ -21,6 +21,6 @@
 nnn -p /tmp/picked
 
 if [ -f /tmp/picked ]; then
-    cat /tmp/picked | tr '\0' '\n'
+    tr '\0' '\n' < /tmp/picked
     rm /tmp/picked
 fi

plugins/readit

@@ -13,11 +13,11 @@ if ! [ -z "$1" ]; then
         # Convert using pdftotext
         pdftotext -nopgbrk -layout "$1" - | sed 's/\xe2\x80\x8b//g' > "$tmpf".txt
 
-        pico2wave -w "$tmpf".wav -l en-GB "$(cat "$tmpf".txt | tr '\n' ' ')"
+        pico2wave -w "$tmpf".wav -l en-GB "$(tr '\n' ' ' < "$tmpf".txt)"
 
         rm "$tmpf".txt
     else
-        pico2wave -w "$tmpf".wav -l en-GB "$(cat "$1" | tr '\n' ' ')"
+        pico2wave -w "$tmpf".wav -l en-GB "$(tr '\n' ' ' < "$1")"
     fi
 
     # to jump around and note the time

src/nnn.c

@@ -891,7 +891,7 @@ static bool listselfile(void)
 	if (!sb.st_size)
 		return FALSE;
 
-	snprintf(g_buf, CMD_LEN_MAX, "cat %s | tr \'\\0\' \'\\n\'", g_selpath);
+	snprintf(g_buf, CMD_LEN_MAX, "tr \'\\0\' \'\\n\' < %s", g_selpath);
 	spawn(utils[SH_EXEC], g_buf, NULL, NULL, F_CLI | F_CONFIRM);
 
 	return TRUE;
@@ -1346,7 +1346,7 @@ static bool cpmv_rename(int choice, const char *path)
 
 	/* selsafe() returned TRUE for this to be called */
 	if (!selbufpos) {
-		snprintf(buf, sizeof(buf), "cat %s | tr '\\0' '\\n' > %s", g_selpath, g_tmpfpath);
+		snprintf(buf, sizeof(buf), "tr '\\0' '\\n' < %s > %s", g_selpath, g_tmpfpath);
 		spawn(utils[SH_EXEC], buf, NULL, NULL, F_CLI);
 
 		count = lines_in_file(fd, buf, sizeof(buf));