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+====== Exam 2014/09/08 ======
+**Text:**\\
+The comman ''ls -la'' provides the following output:
+<code bash>
+total 56
+drwxr-xr-x  4 scanzio scanzio  4096 dic  6 18:39 .
+drwxrwxrwt 26 root    root    20480 dic  6 18:39 ..
+drwxr-xr-x  2 scanzio scanzio  4096 dic  6 18:38 current
+drwxr-xr-x  2 scanzio scanzio  4096 dic  6 18:37 documents
+-rw-r--r--  1 scanzio scanzio 11887 dic  6 18:39 .emacs
+-rw-r--r--  1 scanzio scanzio  8980 dic  6 18:38 examples.desktop
+lrwxrwxrwx  1 scanzio scanzio    10 dic  6 18:39 so -> current/so
+</code>
+Write a bash script that receives in input a list of directory names in the command line, and that for each directory (given the list of its content obtained through the ''ls -al'' command) performs the following operations:
+  * if the //directory entry// is a //directory//, it prints its name and the number of sub-directories it contains (in a recursive way).
+  * if the //directory entry// is a //regular file//, it prints the name of the owner, its dimension and its name.
+  * if the //directory entry// is a //symbolic link//, it prints the creation date, its name and the name referred by the link (without the symbol ''- >'').
+**Solution:**\\
+<code bash 20140908.sh>
+#!/bin/bash
+# Control if the number of parameters is correct (i.e., at least one parameter is needed)
+if [ $# -eq 0 ]
+then
+   echo "Usage: $0 <list_of_directories>"
+   exit 1
+fi
+# Control that all the parameters are effectivelly directories
+for i in $*
+do
+    if [ ! -d $i ]
+    then
+        echo "$i is not a directly"
+        exit 2
+    fi
+done
+for dir in $* # Cycle on all the directories
+do
+    ls -la $dir > .tmp_$$ # Output of ls -al in the hidden file named .tmp_$$
+    while read line #Ciclo su tutte le linee del file
+    do
+        name=$(echo $line | cut -d " " -f 9)
+        if [ "$name" = "." -o "$name" = ".." ]
+        then
+            continue
+        fi
+        f1=$(echo $line | cut -d " " -f 1) # Extraction of the first column
+        # Caso directory
+        # Si fa notare che il comando grep se fa il match almeno di un'espressione regolare fa una exit 0 (settando il valore di $?, valori di ritorno dell'ultimo comando, a 0), altrimenti $? e' uguale a 1
+        echo $f1 | grep "^d" > /dev/null
+        if [ $? -eq 0 ]
+        then
+            dname=$(echo $line | cut -d " " -f 9)
+            nsubdirs=$(find $dir/$dname -type d | wc -l)
+            echo $dir/$dname is a directory having $nsubdirs subdirs
+        fi
+        # Caso file
+        echo $f1 | grep "^-" > /dev/null
+        if [ $? -eq 0 ]
+        then
+            name=$(echo $line | cut -d " " -f 9)
+            owner=$(echo $line | cut -d " " -f 3)
+            size=$(echo $line | cut -d " " -f 5)
+            echo $name is a regular file, its owner is $owner and its size is $size bytes
+        fi
+        # Caso link simbolico
+        echo $f1 | grep "^l" > /dev/null
+        if [ $? -eq 0 ]
+        then
+            name=$(echo $line | cut -d " " -f 9)
+            date=$(echo $line | cut -d " " -f 6,7,8)
+            reference=$(echo $line | cut -d " " -f 11)
+            echo $name is a link created on $date, it refers to $reference
+        fi
+    done < .tmp_$$
+done
+rm .tmp_$$
+exit 0
+</code>
+**Output:**\\
+<code bash>
+$ ./20140908.sh x
+x/current is a directory having 1 subdirs
+x/documents is a directory having 1 subdirs
+.emacs is a regular file, its owner is scanzio and its size is 11887 bytes
+examples.desktop is a regular file, its owner is scanzio and its size is 8980 bytes
+so is a link created on dic 6 18:39, it refers to current/so
+</code>

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