microshell.c

Projekt na systemy operacyjne. Microshell dla linuxa w języku c.

Microshell

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+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#define MAXARGS 256
+
+int main()
+{
+        char* usrinput = NULL;
+        int n = 0;    
+        while (1)
+        {
+				
+				char pwd[100];
+				getcwd(pwd,100);
+	
+                printf("[%s] &",pwd);
+ 
+                char readcomm = getline(&usrinput, &n, stdin);
+
+                if (usrinput[readcomm-1] == '\n')
+                {
+                        usrinput[readcomm-1] = 0;
+                }
+ 
+                char* command[MAXARGS + 1] = {strtok(usrinput, " "), 0 };
+                char* ptr;
+                int i = 1;
+                while (ptr = strtok(NULL, " "))
+                {			
+                        command[i] = ptr;
+                        i++;
+                }
+                if (strcmp(command[0], "exit")==0) 
+                {		
+						return 0;
+                }
+                
+                if (strcmp(command[0], "help")==0) 
+				{
+                        printf("\n========================================\n=          Arkadiusz Charliński        =\n");
+                        printf("= własna implemantacja: exit, help, cd =\n========================================\n\n");
+                        continue;
+						exit(EXIT_FAILURE);
+                }
+ 
+                if (strcmp(command[0],"cd") == 0)
+                {
+					if (command[1]==NULL)
+					{
+						chdir(getenv("HOME"));
+						continue;
+						exit(EXIT_FAILURE);
+					}
+				
+					else
+					{
+						chdir(command[1]);
+						continue;
+						exit(EXIT_FAILURE);
+					}
+				}
+				
+                int pid = fork();
+                 
+                if (pid==0 && strcmp(command[0],"help") !=0 && strcmp(command[0],"cd") !=0 && strcmp(command[0],"exit") !=0) 
+                {
+                        execvp(command[0], command);
+                        perror(command[0]);
+                        exit(EXIT_FAILURE);
+                }
+                 else 
+                {
+                      waitpid(pid, NULL, 0); 
+                }
+ 
+		}
+    return 0;
+}