diff --git a/4-ShellP2/.dshlib.c.swp b/4-ShellP2/.dshlib.c.swp
new file mode 100644
index 0000000000000000000000000000000000000000..7b1c66f6e023becd69f71d5ed390e4de36e131a8
Binary files /dev/null and b/4-ShellP2/.dshlib.c.swp differ
diff --git a/4-ShellP2/bats/assignment_test.sh b/4-ShellP2/bats/assignment_test.sh
new file mode 100644
index 0000000000000000000000000000000000000000..30b12ec1661cd179396f1e2ee3fd8ef39de7eb96
--- /dev/null
+++ b/4-ShellP2/bats/assignment_test.sh
@@ -0,0 +1,118 @@
+#!/usr/bin/env bats
+
+############################ DO NOT EDIT THIS FILE #####################################
+# File: assignement_tests.sh
+#
+# DO NOT EDIT THIS FILE
+#
+# Add/Edit Student tests in student_tests.sh
+#
+# All tests in this file must pass - it is used as part of grading!
+########################################################################################
+
+@test "Change directory" {
+ current=$(pwd)
+
+ cd /tmp
+ mkdir -p dsh-test
+
+ run "${current}/dsh" <<EOF
+cd dsh-test
+pwd
+EOF
+
+ # Strip all whitespace (spaces, tabs, newlines) from the output
+ stripped_output=$(echo "$output" | tr -d '[:space:]')
+
+ # Expected output with all whitespace removed for easier matching
+ expected_output="/tmp/dsh-testdsh2>dsh2>dsh2>cmdloopreturned0"
+
+ # These echo commands will help with debugging and will only print
+ #if the test fails
+ echo "Captured stdout:"
+ echo "Output: $output"
+ echo "Exit Status: $status"
+ echo "${stripped_output} -> ${expected_output}"
+
+ # Check exact match
+ [ "$stripped_output" = "$expected_output" ]
+
+ # Assertions
+ [ "$status" -eq 0 ]
+}
+
+@test "Change directory - no args" {
+ current=$(pwd)
+
+ cd /tmp
+ mkdir -p dsh-test
+
+ run "${current}/dsh" <<EOF
+cd
+pwd
+EOF
+
+ # Strip all whitespace (spaces, tabs, newlines) from the output
+ stripped_output=$(echo "$output" | tr -d '[:space:]')
+
+ # Expected output with all whitespace removed for easier matching
+ expected_output="/tmpdsh2>dsh2>dsh2>cmdloopreturned0"
+
+ # These echo commands will help with debugging and will only print
+ #if the test fails
+ echo "Captured stdout:"
+ echo "Output: $output"
+ echo "Exit Status: $status"
+ echo "${stripped_output} -> ${expected_output}"
+
+ # Check exact match
+ [ "$stripped_output" = "$expected_output" ]
+
+ # Assertions
+ [ "$status" -eq 0 ]
+}
+
+
+@test "Which which ... which?" {
+ run "./dsh" <<EOF
+which which
+EOF
+
+ # Strip all whitespace (spaces, tabs, newlines) from the output
+ stripped_output=$(echo "$output" | tr -d '[:space:]')
+
+ # Expected output with all whitespace removed for easier matching
+ expected_output="/usr/bin/whichdsh2>dsh2>cmdloopreturned0"
+
+ # These echo commands will help with debugging and will only print
+ #if the test fails
+ echo "Captured stdout:"
+ echo "Output: $output"
+ echo "Exit Status: $status"
+ echo "${stripped_output} -> ${expected_output}"
+
+ # Check exact match
+ [ "$stripped_output" = "$expected_output" ]
+}
+
+@test "It handles quoted spaces" {
+ run "./dsh" <<EOF
+ echo " hello world "
+EOF
+
+ # Strip all whitespace (spaces, tabs, newlines) from the output
+ stripped_output=$(echo "$output" | tr -d '\t\n\r\f\v')
+
+ # Expected output with all whitespace removed for easier matching
+ expected_output=" hello world dsh2> dsh2> cmd loop returned 0"
+
+ # These echo commands will help with debugging and will only print
+ #if the test fails
+ echo "Captured stdout:"
+ echo "Output: $output"
+ echo "Exit Status: $status"
+ echo "${stripped_output} -> ${expected_output}"
+
+ # Check exact match
+ [ "$stripped_output" = "$expected_output" ]
+}
diff --git a/4-ShellP2/bats/student_test.sh b/4-ShellP2/bats/student_test.sh
new file mode 100644
index 0000000000000000000000000000000000000000..638bc341446f7580a80c2aff52971b8023407ea8
--- /dev/null
+++ b/4-ShellP2/bats/student_test.sh
@@ -0,0 +1,14 @@
+#!/usr/bin/env bats
+
+# File: student_tests.sh
+#
+# Create your unit tests suit in this file
+
+@test "Example: check ls runs without errors" {
+ run ./dsh <<EOF
+ls
+EOF
+
+ # Assertions
+ [ "$status" -eq 0 ]
+}
diff --git a/4-ShellP2/dragon.c b/4-ShellP2/dragon.c
new file mode 100644
index 0000000000000000000000000000000000000000..b5ac87f2c407c82436f71ae95472bccb5ff0b9be
--- /dev/null
+++ b/4-ShellP2/dragon.c
@@ -0,0 +1,37 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "dshlib.h"
+
+// EXTRA CREDIT - print the drexel dragon from the readme.md
+extern void print_dragon(){
+ // TODO implement
+ FILE *dragon = fopen("dragon.txt", "r");
+ if (dragon == NULL) {
+ return;
+ }
+
+ char *s = NULL;
+ size_t nbyte;
+ ssize_t nchar;
+
+ while (1) {
+ nchar = getline(&s, &nbyte, dragon);
+ if (nchar == -1) { // end of file reached
+ break;
+ }
+ if (nchar == 0) {
+ continue;
+ }
+ if (s == NULL) { // out of memory
+ exit(1);
+ }
+ if (s[nchar - 1] == '\n') {
+ s[nchar - 1] = '\0'; // remove newline
+ nchar--; // newline removed
+ }
+
+ printf("%s\n", s);
+ }
+ free(s);
+ fclose(dragon);
+}
diff --git a/4-ShellP2/dragon.txt b/4-ShellP2/dragon.txt
new file mode 100644
index 0000000000000000000000000000000000000000..a9177fd41bb14d2fa0fd439742e74d3f61f60d2d
--- /dev/null
+++ b/4-ShellP2/dragon.txt
@@ -0,0 +1,38 @@
+ @%%%%
+ %%%%%%
+ %%%%%%
+ % %%%%%%% @
+ %%%%%%%%%% %%%%%%%
+ %%%%%%% %%%%@ %%%%%%%%%%%%@ %%%%%% @%%%%
+ %%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%% %%%%%%%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%% %%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%@ @%%%%%%%%%%%%%%%%%% %%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%@%%%%%%@
+ %%%%%%%%@ %%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%% %%
+ %%%%%%%%%%%%% %%@%%%%%%%%%%%% %%%%%%%%%%% %%%%%%%%%%%% @%
+ %%%%%%%%%% %%% %%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%
+ %%%%%%%%% % %%%%%%%%%%%%% %%%%%%%%%%%%@%%%%%%%%%%%
+%%%%%%%%%@ % %%%%%%%%%%%%% @%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%@ %%@%%%%%%%%%%%% @%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%@ %%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%% %%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%
+%%%%%%%%%@ @%%%%%%%%%%%%%% %%%%%%%%%%%%@ %%%% %%%%%%%%%%%%%%%%% %%%%%%%%
+%%%%%%%%%% %%%%%%%%%%%%%%%%% %%%%%%%%%%%%% %%%%%%%%%%%%%%%%%% %%%%%%%%%
+%%%%%%%%%@%%@ %%%%%%%%%%%%%%%%@ %%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%% %%
+ %%%%%%%%%% % %%%%%%%%%%%%%%@ %%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%% %%
+ %%%%%%%%%%%% @ %%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%
+ %%%%%%%%%%%%% %% % %@ %%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%
+ %%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%% @%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%
+ @%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%% %%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%% @%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%% @%@% @%%%%%%%%%%%%%%%%%% %%%
+ %%%%%%%%%%%%%%% %%%%%%%%%% %%%%%%%%%%%%%%% %
+ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%
+ %%%%%%%%%%%%%%%%%%%%%%%%%% %%%% %%% %%%%%%%%%% %%%@
+ %%%%%%%%%%%%%%%%%%% %%%%%% %% %%%%%%%%%%%%%@
+ %%%%%%%@
diff --git a/4-ShellP2/dsh b/4-ShellP2/dsh
new file mode 100755
index 0000000000000000000000000000000000000000..bc71f23f06921448398c90d8c8ef9609de2dbfd4
Binary files /dev/null and b/4-ShellP2/dsh differ
diff --git a/4-ShellP2/dsh_cli.c b/4-ShellP2/dsh_cli.c
new file mode 100644
index 0000000000000000000000000000000000000000..ef8029b132addbe6e3428c7547bfc37796e15669
--- /dev/null
+++ b/4-ShellP2/dsh_cli.c
@@ -0,0 +1,13 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "dshlib.h"
+
+/* DO NOT EDIT
+ * main() logic moved to exec_local_cmd_loop() in dshlib.c
+*/
+int main(){
+ int rc = exec_local_cmd_loop();
+ printf("cmd loop returned %d\n", rc);
+}
diff --git a/4-ShellP2/dshlib.c b/4-ShellP2/dshlib.c
new file mode 100644
index 0000000000000000000000000000000000000000..c168f6dc0858734439c9fa1cbd0fd50290b4fcea
--- /dev/null
+++ b/4-ShellP2/dshlib.c
@@ -0,0 +1,275 @@
+#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 <errno.h>
+#include "dshlib.h"
+
+int numInstanceOf(char *str, const char c) {
+ int count = 0;
+ while (*str != '\0') {
+ if (*str == c) count++;
+ str++;
+ }
+ return count;
+}
+
+int alloc_cmd_buff(cmd_buff_t *cmd_buff) {
+ if (cmd_buff == NULL) {
+ return ERR_MEMORY;
+ }
+ cmd_buff->argc = 0;
+
+ cmd_buff->argv = (char**)malloc(CMD_ARGV_MAX * sizeof(char *));
+ if (cmd_buff->argv == NULL) {
+ free(cmd_buff);
+ return ERR_MEMORY;
+ }
+
+ for (int i = 0; i < CMD_ARGV_MAX; i++) {
+ cmd_buff->argv[i] = (char *)malloc(ARG_MAX);
+ if (cmd_buff->argv[i] == NULL) {
+ for (int j = 0; j < i; j++) {
+ free(cmd_buff->argv[j]);
+ }
+ free(cmd_buff->argv);
+ return ERR_MEMORY;
+ }
+ }
+
+ cmd_buff->_cmd_buffer = (char *)malloc(SH_CMD_MAX);
+ if (cmd_buff->_cmd_buffer == NULL) {
+ free(cmd_buff->_cmd_buffer);
+ for (int i = 0; i < CMD_ARGV_MAX; i++) {
+ free(cmd_buff->argv[i]);
+ }
+ free(cmd_buff->argv);
+ return ERR_MEMORY;
+ }
+
+
+ return OK_EXIT;
+}
+
+int free_cmd_buff(cmd_buff_t *cmd_buff) {
+ free(cmd_buff->_cmd_buffer);
+
+ for (int i = 0; i < CMD_ARGV_MAX - 1; i++) free(cmd_buff->argv[i]);
+ free(cmd_buff);
+ return OK_EXIT;
+}
+
+int clear_cmd_buff(cmd_buff_t *cmd_buff) {
+ cmd_buff->argc = 0;
+ free(cmd_buff->_cmd_buffer);
+
+ for (int i = 0; i < CMD_ARGV_MAX; i++) cmd_buff->argv[i] = NULL;
+ return OK_EXIT;
+}
+
+char* trim_whitespace(char *str) {
+ int start = 0;
+ while (isspace((unsigned char)str[start])) {
+ start++;
+ }
+
+ int end = strlen(str) - 1;
+ while (end > start && isspace((unsigned char)str[end])) {
+ end--;
+ }
+
+ int j = 0;
+ for (int i = start; i <= end; i++) {
+ str[j++] = str[i];
+ }
+ str[j] = '\0';
+
+ return str;
+}
+
+int build_cmd_buff(char *cmd_line, cmd_buff_t *cmd_buff) {
+ if ((int)strlen(cmd_line) > SH_CMD_MAX) return ERR_CMD_OR_ARGS_TOO_BIG;
+
+ if ((int)strlen(cmd_line) == 0) return WARN_NO_CMDS;
+
+ cmd_buff->_cmd_buffer = strdup(trim_whitespace(cmd_line));
+ if (cmd_buff->_cmd_buffer == NULL) {
+ free(cmd_buff);
+ return ERR_MEMORY;
+ }
+
+ char *token = cmd_buff->_cmd_buffer;
+ bool quotes = false;
+ char *p = NULL;
+
+ while (*token) {
+ if (*token == DOUBLE_QUOTE_CHAR) {
+ quotes = !quotes;
+ if (quotes) p = token + 1;
+ else *token = '\0';
+ } else if (!quotes && (*token == SPACE_CHAR || *token == '\t')) {
+ *token = '\0';
+
+ if (p != NULL) {
+ cmd_buff->argv[cmd_buff->argc++] = p;
+ p = NULL;
+ }
+ } else if (p == NULL) {
+ p = token;
+ }
+ token++;
+ }
+
+ if (p != NULL) cmd_buff->argv[cmd_buff->argc++] = p;
+
+ cmd_buff->argv[cmd_buff->argc] = NULL;
+ return OK_EXIT;
+}
+/*
+ * Implement your exec_local_cmd_loop function by building a loop that prompts the
+ * user for input. Use the SH_PROMPT constant from dshlib.h and then
+ * use fgets to accept user input.
+ *
+ * while(1){
+ * printf("%s", SH_PROMPT);
+ * if (fgets(cmd_buff, ARG_MAX, stdin) == NULL){
+ * printf("\n");
+ * break;
+ * }
+ * //remove the trailing \n from cmd_buff
+ * cmd_buff[strcspn(cmd_buff,"\n")] = '\0';
+ *
+ * //IMPLEMENT THE REST OF THE REQUIREMENTS
+ * }
+ *
+ * Also, use the constants in the dshlib.h in this code.
+ * SH_CMD_MAX maximum buffer size for user input
+ * EXIT_CMD constant that terminates the dsh program
+ * SH_PROMPT the shell prompt
+ * OK the command was parsed properly
+ * WARN_NO_CMDS the user command was empty
+ * ERR_TOO_MANY_COMMANDS too many pipes used
+ * ERR_MEMORY dynamic memory management failure
+ *
+ * errors returned
+ * OK No error
+ * ERR_MEMORY Dynamic memory management failure
+ * WARN_NO_CMDS No commands parsed
+ * ERR_TOO_MANY_COMMANDS too many pipes used
+ *
+ * console messages
+ * CMD_WARN_NO_CMD print on WARN_NO_CMDS
+ * CMD_ERR_PIPE_LIMIT print on ERR_TOO_MANY_COMMANDS
+ * CMD_ERR_EXECUTE print on execution failure of external command
+ *
+ * Standard Library Functions You Might Want To Consider Using (assignment 1+)
+ * malloc(), free(), strlen(), fgets(), strcspn(), printf()
+ *
+ * Standard Library Functions You Might Want To Consider Using (assignment 2+)
+ * fork(), execvp(), exit(), chdir()
+ */
+int exec_local_cmd_loop()
+{
+ char *cmd_buff = malloc(ARG_MAX * sizeof(char));
+ int rc = 0;
+ cmd_buff_t *cmd = malloc(CMD_ARGV_MAX * sizeof(char *));
+
+ if ((rc = alloc_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+
+ // TODO IMPLEMENT MAIN LOOP
+ while(1){
+ printf("%s", SH_PROMPT);
+ if (fgets(cmd_buff, ARG_MAX, stdin) == NULL){
+ printf("\n");
+ break;
+ }
+ //remove the trailing \n from cmd_buff
+ cmd_buff[strcspn(cmd_buff,"\n")] = '\0';
+
+ //IMPLEMENT THE REST OF THE REQUIREMENTS
+ if (strcmp(cmd_buff, EXIT_CMD) == 0) {
+ exit(rc);
+ }
+
+ if (strcmp(cmd_buff, "rc") == 0) {
+ printf("%d\n", rc);
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ continue;
+ }
+
+ if (strcmp(cmd_buff, "\0") == 0) {
+ rc = WARN_NO_CMDS;
+ printf(CMD_WARN_NO_CMD);
+ //if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ continue;
+ }
+
+ // TODO IMPLEMENT parsing input to cmd_buff_t *cmd_buff
+ if ((rc = build_cmd_buff(cmd_buff, cmd)) != OK_EXIT) {
+ exit(rc);
+ rc = 0;
+ }
+ /*
+ if (strcmp(cmd->argv[0], "echo") == 0) {
+ for (int i = 1; i < CMD_ARGV_MAX; i++) {
+ printf("%s ", cmd->argv[i]);
+ }
+ printf("\n");
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ continue;
+ }*/
+
+ // TODO IMPLEMENT if built-in command, execute builtin logic for exit, cd (extra credit: dragon)
+ if (strcmp(cmd_buff, "dragon") == 0) {
+ print_dragon();
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ rc = 0;
+ continue;
+ }
+
+ // the cd command should chdir to the provided directory; if no directory is provided, do nothing
+ if (strcmp(cmd->argv[0], "cd") == 0) {
+ if (cmd->argc < 2) {
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ rc = 0;
+ continue;
+ }
+ if (chdir(cmd->argv[1]) != 0) {
+ perror("chdir failed");
+ rc = 1;
+ }
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ rc = 0;
+ continue;
+ }
+
+ // TODO IMPLEMENT if not built-in command, fork/exec as an external command
+ // for example, if the user input is "ls -l", you would fork/exec the command "ls" with the arg "-l"
+ pid_t pid = fork();
+ if (pid < 0) {
+ printf("fork failed");
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ continue;
+ } else if (pid == 0) {
+ execvp(cmd->argv[0], cmd->argv);
+ perror(CMD_ERR_EXECUTE);
+ exit(1);
+ } else {
+ int status;
+ waitpid(pid, &status, 0);
+ if (WIFEXITED(status)) {
+ rc = WEXITSTATUS(status);
+ } else {
+ rc = 1;
+ }
+ }
+ if ((rc = clear_cmd_buff(cmd)) != OK_EXIT) exit(rc);
+ }
+ free(cmd_buff);
+ free_cmd_buff(cmd);
+ return OK;
+}
diff --git a/4-ShellP2/dshlib.h b/4-ShellP2/dshlib.h
new file mode 100644
index 0000000000000000000000000000000000000000..df2f9a4d0061aee7f57b947ccba254178756c4b4
--- /dev/null
+++ b/4-ShellP2/dshlib.h
@@ -0,0 +1,85 @@
+#ifndef __DSHLIB_H__
+ #define __DSHLIB_H__
+
+
+//Constants for command structure sizes
+#define EXE_MAX 64
+#define ARG_MAX 256
+#define CMD_MAX 8
+#define CMD_ARGV_MAX (CMD_MAX + 1)
+// Longest command that can be read from the shell
+#define SH_CMD_MAX EXE_MAX + ARG_MAX
+
+typedef struct cmd_buff
+{
+ int argc;
+ char **argv;
+ char *_cmd_buffer;
+} cmd_buff_t;
+
+/* WIP - Move to next assignment
+#define N_ARG_MAX 15 //MAX number of args for a command
+typedef struct command{
+ char exe [EXE_MAX];
+ char args[ARG_MAX];
+ int argc;
+ char *argv[N_ARG_MAX + 1]; //last argv[LAST] must be \0
+}command_t;
+*/
+
+
+//Special character #defines
+#define SPACE_CHAR ' '
+#define SPACE_STRING " "
+#define PIPE_CHAR '|'
+#define PIPE_STRING "|"
+#define DOUBLE_QUOTE_CHAR '"'
+
+#define SH_PROMPT "dsh2> "
+#define EXIT_CMD "exit"
+
+//Standard Return Codes
+#define OK 0
+#define WARN_NO_CMDS -1
+#define ERR_TOO_MANY_COMMANDS -2
+#define ERR_CMD_OR_ARGS_TOO_BIG -3
+#define ERR_CMD_ARGS_BAD -4 //for extra credit
+#define ERR_MEMORY -5
+#define ERR_EXEC_CMD -6
+#define OK_EXIT -7
+
+//prototypes
+int alloc_cmd_buff();
+int free_cmd_buff(cmd_buff_t *);
+int clear_cmd_buff(cmd_buff_t *);
+int build_cmd_buff(char *, cmd_buff_t *);
+void exeCD(char *path);
+void execFork(char *);
+extern void print_dragon();
+
+//built in command stuff
+typedef enum {
+ BI_CMD_EXIT,
+ BI_CMD_DRAGON,
+ BI_CMD_CD,
+ BI_NOT_BI,
+ BI_EXECUTED,
+ BI_RC,
+} Built_In_Cmds;
+Built_In_Cmds match_command(const char *input);
+Built_In_Cmds exec_built_in_cmd(cmd_buff_t *cmd);
+
+//main execution context
+int exec_local_cmd_loop();
+int exec_cmd(cmd_buff_t *cmd);
+
+
+
+
+//output constants
+#define CMD_OK_HEADER "PARSED COMMAND LINE - TOTAL COMMANDS %d\n"
+#define CMD_WARN_NO_CMD "warning: no commands provided\n"
+#define CMD_ERR_PIPE_LIMIT "error: piping limited to %d commands\n"
+#define CMD_ERR_EXECUTE "Command not found in PATH\n"
+
+#endif
diff --git a/4-ShellP2/makefile b/4-ShellP2/makefile
new file mode 100644
index 0000000000000000000000000000000000000000..a079ef4946ce8578836606ceab3f553b305b1875
--- /dev/null
+++ b/4-ShellP2/makefile
@@ -0,0 +1,31 @@
+# Compiler settings
+CC = gcc
+CFLAGS = -Wall -Wextra -g
+
+# Target executable name
+TARGET = dsh
+
+# Find all source and header files
+SRCS = $(wildcard *.c)
+HDRS = $(wildcard *.h)
+
+# Default target
+all: $(TARGET)
+
+# Compile source to executable
+$(TARGET): $(SRCS) $(HDRS)
+ $(CC) $(CFLAGS) -o $(TARGET) $(SRCS)
+
+# Clean up build files
+clean:
+ rm -f $(TARGET)
+
+test:
+ bats $(wildcard ./bats/*.sh)
+
+valgrind:
+ echo "pwd\nexit" | valgrind --leak-check=full --show-leak-kinds=all --error-exitcode=1 ./$(TARGET)
+ echo "pwd\nexit" | valgrind --tool=helgrind --error-exitcode=1 ./$(TARGET)
+
+# Phony targets
+.PHONY: all clean test