DONE

src/cmd.c

@@ -68,6 +68,7 @@ static int parse_simple(simple_command_t *s, int level, command_t *father)
 		shell_exit();
 
 	} else if (strcmp(command, "cd") == 0) {
+		/* Saving the old output, redirecting if the case, readjusting the ouput to the old one */
 		int save = dup(STDOUT_FILENO);
 		char *out = get_word(s->out);
 		int out_fd = open(out, O_WRONLY | O_CREAT | O_TRUNC, 0644);
@@ -83,6 +84,7 @@ static int parse_simple(simple_command_t *s, int level, command_t *father)
 		return status;
 
 	} else {
+		/* Getting the environment variable and modifying  */
 		char *envir_var = get_word(s->verb);
 
 		if (strchr(envir_var, '=') != NULL) {
@@ -110,6 +112,7 @@ static int parse_simple(simple_command_t *s, int level, command_t *father)
 			return -1;
 
 		} else if (pid == 0) {
+			/* Saving the in */
 			char *in = get_word(s->in);
 			int in_fd = open(in, O_RDONLY);
 
@@ -117,6 +120,7 @@ static int parse_simple(simple_command_t *s, int level, command_t *father)
 			free(in);
 
 			if (s->out != NULL && s->err != NULL && strcmp(get_word(s->out), get_word(s->err)) == 0) {
+				/* For the &> redirection */
 				char *out = get_word(s->out);
 				int out_fd;
 
@@ -130,6 +134,7 @@ static int parse_simple(simple_command_t *s, int level, command_t *father)
 				free(out);
 
 			} else {
+				/* Opening the out and error if they exists */
 				if (s->out != NULL) {
 					char *out = get_word(s->out);
 					int out_fd;
@@ -157,6 +162,7 @@ static int parse_simple(simple_command_t *s, int level, command_t *father)
 				}
 			}
 
+			/* Getting the commmand and executing it. If error, exit */
 			int argc = 0;
 			char **argv = get_argv(s, &argc);
 
@@ -187,6 +193,7 @@ static bool run_in_parallel(command_t *cmd1, command_t *cmd2, int level,
 		command_t *father)
 {
 	/* TODO: Execute cmd1 and cmd2 simultaneously. */
+	/* Two kids, both executing down the tree command */
 
 	pid_t pid1 = fork();
 
@@ -221,8 +228,11 @@ static bool run_on_pipe(command_t *cmd1, command_t *cmd2, int level,
 
 	int pipefd[2];
 
+	/* Pipe for in - out functionality */
 	pipe(pipefd);
 
+	/* The first end. Closing the end we do not use, */
+	/* Pointing the output of the first process to the in of the second */
 	pid_t pid1 = fork();
 
 	if (pid1 == 0) {
@@ -235,6 +245,8 @@ static bool run_on_pipe(command_t *cmd1, command_t *cmd2, int level,
 		exit(stat);
 	}
 
+	/* Second end. */
+	/* Taking the input from the ouput end of the pipe (reading one) */
 	pid_t pid2 = fork();
 
 	if (pid2 == 0) {