implementing shell tools exercise is compleat

Author: HilolaRustam

implement-shell-tools/cat/my-cat.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+
+set -euo pipefail
+
+number_lines=false 
+number_non_empty=false
+
+# check for flags
+if [ "${1:-}" = "-n" ]; then 
+  number_lines=true
+  shift
+elif [ "${1:-}" = "-b" ]; then
+  number_non_empty=true
+  shift
+fi
+
+count=1
+
+# Loop through all files
+
+for file in "$@"
+do
+  while IFS= read -r line
+  do
+    if [ "$number_lines" = true ]; then
+    echo "$count $line"
+    count=$((count+1))
+
+    else if [ "$number_non_empty" = true ]; then
+      if [ -n "$line" ]; then
+        echo "$count $line"
+        count=$((count+1))
+      else
+        echo ""
+       fi
+
+     else
+       echo "$line"
+     fi   
+   fi
+  done < "$file" 
+done

implement-shell-tools/ls/my-ls.sh

@@ -0,0 +1,34 @@
+  #!/bin/bash
+ set -euo pipefail
+
+show_all=false
+
+# handle -a
+if [ "${1:-}" = "-a" ]; then
+  show_all=true
+  shift
+fi 
+
+# directory (default current)
+ dir="."
+
+ if [ "${1:-}" != "" ]; then
+   dir="$1"
+ fi 
+
+ #choose pattern
+ if [ "$show_all" = true ]; then 
+   files="$dir"/.*
+ else
+   files="$dir"/*
+ fi
+ # loop      
+ for file in $files
+ do 
+   name="$(basename "$file")"
+
+   if [ "$name" = "." ] || [ "$name" = ".." ]; then 
+   continue
+   fi
+   echo "$name"
+  done  

implement-shell-tools/wc/my-wc.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+set -euo pipefail
+
+flag="all"
+
+if [ "${1:-}" = "-l" ]; then 
+  flag="l"
+  shift
+elif [ "${1:-}" = "-w" ]; then
+  flag="w"
+  shift
+elif [ "${1:-}" = "-c" ]; then
+  flag="c"
+  shift  
+fi
+
+for file in "$@"
+do 
+  if [ -d "$file" ]; then
+    continue
+  fi
+
+   lines=0
+   words=0
+   chars=0
+
+   while IFS= read -r line 
+   do
+     lines=$((lines + 1))
+     words=$((words + $(echo "$line" | wc -w)))
+     chars=$((chars + ${#line} + 1))
+   done <"$file" 
+
+   if [ "$flag" = "l" ]; then
+    echo "$lines $file"
+   elif [ "$flag" = "w" ]; then
+    echo "$words $file"
+   elif [ "$flag" = "c" ]; then
+    echo "$chars $file"
+   else 
+    echo "$lines $words $chars $file" 
+   fi    
+done
+