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+====== File reading (Example 1) ======
+**Concepts:**\\
+Function for open, close and read a file. Example on how to read a file row-by-row, word-by-word, character-by-character and how to read a structured file (where field of different type are save in each row of the file).
+**Text:**\\
+Implements a C program that:
+  * Reads the following file:
+<file txt file.txt>
+First row
+Second row
+</file>
+    * a row at a time (row-by-row)
+    * a word at a time (word-by-word)
+    * a character at a time (character-by-character)
+  * The program must also reads the following file, where each row is structured and composed of a string (a name), an integer number and a real number:
+<file txt file2.txt>
+Jules 122333 23.5
+Laia 122334 29.5
+</file>
+  * The content read from the two files must be printed on the screen (in the case the file is read character-by-character, a space must be printed to separate characters)
+**Video solution:**\\
+Video with the explanation of the solution:
+<html>
+<iframe width="560" height="315" src="https://www.youtube.com/embed/gzZB80GH7Fk" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+</html>
+**Soluzion:**\\
+<file C read_file_1.c>
+/* Example on how to read a file row-by-row, word-by-word, character-by-character and how to read
+   a structured file (where field of different type are save in each row of the file). */
+#include <stdio.h>
+#include <stdlib.h>
+#define LEN 50
+int main()
+{
+    FILE *fp;
+    char row[LEN+1]; /* To read strings of maximum length of 50 characters,
+                        an array of characters of dimension 51 must be declared,
+                        because after the string the termination character '\0' must be stored */
+    char ch;
+    int intValue;
+    float floatValue;
+    /* Reading the content of the file file.txt */
+    /* Opening the file */
+    printf("READING file.txt\n");
+    fp = fopen("file.txt", "r");
+    /* Control if the file has been opened without errors */
+    if (fp == NULL){
+        printf("Error: impossible to open the file file.txt\n");
+        exit(1);
+    }
+    /* Reading the file row-by-row */
+    printf("First reading method:\n");
+    while ( fgets(row, LEN, fp) != NULL ) {
+       printf("READ: %s\n", row);
+    }
+    /* Not recommended */
+    /*
+    rewind(fp);
+    printf("Other reading method:\n");
+    fgets(row, LEN, fp);
+    while ( !feof(fp) ) {
+        printf("READ: %s\n", row);
+        fgets(row, LEN, fp);
+    }
+    */
+    rewind(fp);
+    /* Reading the file word-by-word */
+    printf("Second reading method:\n");
+    while ( fscanf(fp, "%s", row) != EOF ) {
+       printf("READ: %s\n", row);
+    }
+    rewind(fp);
+    /* Reading the file character-by-character */
+    printf("Third reading method:\n");
+    while ( (ch=getc(fp)) != EOF ) {
+       printf("%c ", ch);
+    }
+    fclose(fp); /* Closing the file */
+    /* Reading the content of the file file2.txt */
+    /* Note: the file contains in each row a string, an integer number and a real number */
+    /* Opening the file */
+    printf("\nREADING file2.txt\n");
+    if ( (fp = fopen("file2.txt", "r")) == NULL){
+        printf("Error: impossible to open the file file2.txt\n");
+        exit(1);
+    }
+    /* First reading method */
+    /* Recommended becase it is more compact */
+    printf("First reading method:\n");
+    while ( fscanf(fp, "%s %d %f", row, &intValue, &floatValue) != EOF ) {
+      printf("READ: %s %d %f\n", row, intValue, floatValue);
+    }
+    rewind(fp);
+    /* Second reading method */
+    printf("Second reading method:\n");
+    while ( fgets(row, LEN, fp) != NULL ) { /* E' consigliabile il metodo precedente */
+      sscanf(row, "%s %d %f", row, &intValue, &floatValue);
+      printf("READ: %s %d %f\n", row, intValue, floatValue);
+    }
+    fclose(fp); /* Closing the file */
+    return 0;
+}
+</file>

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