Ready for submission

exercises/ex03/endswith.c

@@ -1,17 +1,11 @@
 /* Example code for Software Systems at Olin College.
-
 Instructions:
-
 1) Fill in the body of endswith so it passes the tests.
-
 You can use any of the functions in string.h
 https://www.tutorialspoint.com/c_standard_library/string_h.htm
-
 2) Remove the TODO comment.
-
 Copyright 2017 Allen Downey
 License: Creative Commons Attribution-ShareAlike 3.0
-
 */
 
 #include <stdio.h>
@@ -20,7 +14,6 @@ License: Creative Commons Attribution-ShareAlike 3.0
 #include <assert.h>
 
 /* endswith: Checks whether s ends with suffix.
-
 s: string
 suffix: string
 returns: 1 if true, 0 otherwise

exercises/ex03/tee.c

@@ -0,0 +1,84 @@
+/*
+ * My implementation of tee.c for Exercise 3, Software Systems 2020.
+ * Reflection and comparison comments are located at the bottom of the file.
+ *
+ * Available argument: -a = append to a file (default: overwrite file)
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <string.h>
+
+
+void writeToFile(char* fileName, char* mode) { // writes given string to given file
+	FILE *f = fopen(fileName, mode); // fileName is the name of file to be edited; mode in which string is to be written (w=write, a=append)
+	char buffer[256];
+
+	if (f == NULL) {
+		printf("An error occurred while opening the file: %s\n", fileName); // prints if f is null
+		exit(1);
+	}
+
+	while (!feof(stdin)) {
+		fgets(buffer, 256, stdin);
+		fprintf(f, "%s", buffer);
+		printf("%s", buffer);
+	}
+
+	fclose(f);
+}
+
+int main(int argc, char *argv[]) {
+	char ch;
+	int i;
+	int append = 0;
+
+	while ((ch = getopt(argc, argv, "a")) != EOF) {
+		switch (ch) {
+			case 'a':
+			append = 1;
+			break;
+			default:
+			puts("Invalid option detected.");
+			break;
+		}
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	for (i = 0; i < argc; i++) {
+		append ? writeToFile(argv[i], "a") : writeToFile(argv[i], "w");
+	}
+
+	return 0;
+}
+
+/*
+ * Reflection
+This was a really daunting task for me to take on. I did not know how to start, and was concerned I wouldn't be able to do this exercise.
+After meeting with a NINJA who told me to think of this problem as a series of smaller problems, I realized I could split up tasks that would make the problem as a whole seem less intimidating.
+Although I started slow, once I figured out the pseudocode, it got easier. The way I broke it down was:
+1. Reading standard input
+2. Allowing for args
+3. Writing to files, etc.
+I began to understand what I was doing and looked up many of these things for more guidance.
+I finished my final implementation of tee in about an hour.
+ *
+ * Next time I'm given some task in C that I don't even know how to begin, I think
+ * I'll remember my experience with this exercise and just focus on breaking the
+ * task into smaller tasks.
+ *
+ * Comparison
+ * Well, looking at the real thing, I've realized that I wasn't too far off which
+ * is really encouraging. The real thing and my code have some similarities, like
+ * using a ternary operator to retrieve the file mode (file_mode = (append_mode ?
+ *  "a" : "w");), but it splits up the smaller parts of tee differently. In fact,
+ *  it doesn't really separate any parts except the parsing of the arguments.
+ *
+ *  I think my code and the real code do mostly the same things though! I was so
+ *  confused about how tee was supposed to work, but I'm relieved to see that I
+ *  didn't completely miss the mark.
+ */