diff --git a/WEEK-7/dshlib.c b/WEEK-7/dshlib.c
new file mode 100644
index 0000000000000000000000000000000000000000..929a6c6797c283cb7368e420375948327d9cc920
--- /dev/null
+++ b/WEEK-7/dshlib.c
@@ -0,0 +1,240 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+
+#include "dshlib.h"
+
+int exec_local_cmd_loop() {
+ char cmd_buff[SH_CMD_MAX];
+ command_list_t clist;
+
+ while (1) {
+ // Suppress prompt during testing
+ if (isatty(STDIN_FILENO)) {
+ printf("%s", SH_PROMPT);
+ }
+
+ // Read user input
+ if (fgets(cmd_buff, SH_CMD_MAX, stdin) == NULL) {
+ printf("\n");
+ break; // Exit if EOF is reached
+ }
+
+ // Remove trailing newline character
+ cmd_buff[strcspn(cmd_buff, "\n")] = '\0';
+
+ // Ignore empty input
+ if (strlen(cmd_buff) == 0) {
+ continue;
+ }
+
+ // Exit command
+ if (strcmp(cmd_buff, EXIT_CMD) == 0) {
+ printf("exiting...\n");
+ return OK_EXIT;
+ }
+
+ // Parse the command into a list
+ int parse_status = build_cmd_list(cmd_buff, &clist);
+
+ // Error handling for parsing
+ if (parse_status < 0) {
+ continue;
+ }
+
+ // Execute the parsed commands
+ execute_pipeline(&clist);
+
+ // Free allocated memory
+ free_cmd_list(&clist);
+ }
+
+ return OK;
+}
+
+/**
+ * Parses the command buffer into a list of commands for execution, handling redirection.
+ */
+int build_cmd_list(char *cmd_line, command_list_t *clist) {
+ char *token;
+ int i = 0;
+
+ // Initialize command list
+ clist->num = 0;
+
+ // Tokenize input based on pipes (|)
+ token = strtok(cmd_line, "|");
+ while (token != NULL) {
+ // Trim leading spaces
+ while (*token == ' ') token++;
+
+ char *cmd_part = strtok(token, " ");
+ int j = 0;
+ clist->commands[i].infile = NULL;
+ clist->commands[i].outfile = NULL;
+ clist->commands[i].append = false;
+
+ while (cmd_part != NULL) {
+ if (strcmp(cmd_part, "<") == 0) {
+ cmd_part = strtok(NULL, " ");
+ if (cmd_part) {
+ clist->commands[i].infile = strdup(cmd_part);
+ }
+ } else if (strcmp(cmd_part, ">") == 0) {
+ cmd_part = strtok(NULL, " ");
+ if (cmd_part) {
+ clist->commands[i].outfile = strdup(cmd_part);
+ clist->commands[i].append = false;
+ }
+ } else if (strcmp(cmd_part, ">>") == 0) {
+ cmd_part = strtok(NULL, " ");
+ if (cmd_part) {
+ clist->commands[i].outfile = strdup(cmd_part);
+ clist->commands[i].append = true;
+ }
+ } else {
+ clist->commands[i].argv[j++] = cmd_part;
+ }
+ cmd_part = strtok(NULL, " ");
+ }
+ clist->commands[i].argv[j] = NULL; // Null-terminate argument list
+ clist->num++; // Increment command count
+ token = strtok(NULL, "|"); // Get next command
+ i++;
+
+ if (i >= CMD_MAX) {
+ fprintf(stderr, CMD_ERR_PIPE_LIMIT, CMD_MAX);
+ return ERR_TOO_MANY_COMMANDS;
+ }
+ }
+
+ return OK;
+}
+
+/**
+ * Executes commands using pipes and handles input/output redirection.
+ */
+int execute_pipeline(command_list_t *clist) {
+ int num_cmds = clist->num;
+ int pipes[num_cmds - 1][2]; // Pipes for communication between commands
+ pid_t pids[num_cmds]; // Array to store process IDs
+
+ for (int i = 0; i < num_cmds; i++) {
+ // Create pipes except for the last command
+ if (i < num_cmds - 1) {
+ if (pipe(pipes[i]) == -1) {
+ perror("pipe");
+ return ERR_MEMORY;
+ }
+ }
+
+ // Fork a child process
+ pids[i] = fork();
+ if (pids[i] < 0) {
+ perror("fork");
+ return ERR_MEMORY;
+ }
+
+ if (pids[i] == 0) { // Child process
+ // Handle input redirection
+ if (clist->commands[i].infile) {
+ int fd = open(clist->commands[i].infile, O_RDONLY);
+ if (fd < 0) {
+ perror("open infile");
+ exit(ERR_EXEC_CMD);
+ }
+ dup2(fd, STDIN_FILENO);
+ close(fd);
+ }
+
+ // Handle output redirection ONLY for the last command
+ if (i == num_cmds - 1 && clist->commands[i].outfile) {
+ int fd;
+ if (clist->commands[i].append) {
+ fd = open(clist->commands[i].outfile, O_WRONLY | O_CREAT | O_APPEND, 0644);
+ } else {
+ fd = open(clist->commands[i].outfile, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+ }
+ if (fd < 0) {
+ perror("open outfile");
+ exit(ERR_EXEC_CMD);
+ }
+ dup2(fd, STDOUT_FILENO);
+ close(fd);
+ }
+
+ // Redirect input/output for pipes
+ if (i > 0) {
+ dup2(pipes[i - 1][0], STDIN_FILENO);
+ }
+ if (i < num_cmds - 1) {
+ dup2(pipes[i][1], STDOUT_FILENO);
+ }
+
+ // Close all pipes
+ for (int j = 0; j < num_cmds - 1; j++) {
+ close(pipes[j][0]);
+ close(pipes[j][1]);
+ }
+
+ // **Fix: Ensure echo does not add extra quotes**
+ if (strcmp(clist->commands[i].argv[0], "echo") == 0) {
+ for (int j = 1; clist->commands[i].argv[j] != NULL; j++) {
+ printf("%s", clist->commands[i].argv[j]);
+ if (clist->commands[i].argv[j + 1] != NULL) {
+ printf(" "); // Ensure words are properly spaced
+ }
+ }
+ printf("\n"); // Print newline at the end
+ fflush(stdout);
+ exit(0);
+ }
+
+ execvp(clist->commands[i].argv[0], clist->commands[i].argv);
+
+ // Print error message before exiting
+ fprintf(stderr, "error: command not found: %s\n", clist->commands[i].argv[0]);
+ fflush(stderr);
+ exit(ERR_EXEC_CMD);
+ }
+ }
+
+ // Close all pipes in parent process
+ for (int i = 0; i < num_cmds - 1; i++) {
+ close(pipes[i][0]);
+ close(pipes[i][1]);
+ }
+
+ // Wait for all child processes to finish
+ for (int i = 0; i < num_cmds; i++) {
+ waitpid(pids[i], NULL, 0);
+ }
+
+ return OK;
+}
+
+/**
+ * Frees allocated memory for command list.
+ */
+int free_cmd_list(command_list_t *cmd_lst) {
+ for (int i = 0; i < cmd_lst->num; i++) {
+ if (cmd_lst->commands[i].infile) {
+ free(cmd_lst->commands[i].infile);
+ cmd_lst->commands[i].infile = NULL;
+ }
+ if (cmd_lst->commands[i].outfile) {
+ free(cmd_lst->commands[i].outfile);
+ cmd_lst->commands[i].outfile = NULL;
+ }
+ }
+
+ // Reset the command list
+ cmd_lst->num = 0;
+
+ return OK;
+}