this is trial practice for git

cmd_execution.c

@@ -15,19 +15,56 @@
  *
  */
 
+/* Implementation of redirection output string.
+ * Developer:  Neha Choudhary
+*/
+
 #include "nektech_shell.h"
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/file.h>
+
+
+extern int redirect_flag;
+extern char *file_name;
 
 /* command Execution.*/ 
 void run_cmd(char *argv[]) 
 { 
    pid_t child_pid; 
+   int fd;
 
    child_pid=fork(); 
    if(child_pid<0){ 
       printf("SOME ERROR HAPPENED IN FORK\n"); 
       exit(2); 
    }else if(child_pid==0){ 
-      if(execvp(argv[0],argv)<0) 
+         /*  redirection output code  */
+     if(redirect_flag){
+         fd=open(file_name, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWGRP | S_IWUSR);
+  /*  Handling of file creation  */
+      if(fd<0)
+        switch(errno){
+        case EACCES:
+              printf("The requested access to the file is not allowed,%s\npermission is denied",file_name);
+              break;
+           case ENOENT:
+              printf("O_CREAT is not set and the named file: %s does not exist",file_name);
+              break;
+           case ENOMEM:
+              printf("Insufficient kernel memory was available.");
+              break;
+                          default:
+                                 printf("Some error is happened in creating the requested file: %s",file_name);
+                                 break;
+        }
+        else{
+        dup2(fd,1);
+        close(fd);
+       }
+ }      
+
+    if(execvp(argv[0],argv)<0) 
          switch(errno){ 
          case ENOENT: 
                printf("COMMAND OR FILENAME NOT FOUND\n"); 

input_parser.c

@@ -23,16 +23,23 @@
 /* Taking User Input and Parsing the input to take action.
  * String operations and intelligece for user input.
  * Developer: Deepika Pandey
-*/ 
+*/
+
+/* Identify Redirection output string from the user input.
+ * Developer:    Neha choudhary   
+*/
+
+int redirect_flag =0;
+char *file_name=NULL;
 
 main() 
 { 
    char cmd[MAX_LEN]; 
    char *cmd_arg[MAX_ARG]; 
    int cmdlen,i,j,tag; 
-
+  
    do{
-      /* init cmd */
+
       for(i=0;i<MAX_LEN;i++) cmd[i]='\0';
 
       printf("NEK Tech>> ");
@@ -42,8 +49,11 @@ main()
       cmdlen--;
       cmd[cmdlen]='\0';
 
+
       for(i=0;i<MAX_ARG;i++) cmd_arg[i]=NULL;
+
       i=0; j=0; tag=0;
+
       while(i<cmdlen && j<MAX_ARG){
          if(cmd[i]==' '){
             cmd[i]='\0';
@@ -53,14 +63,28 @@ main()
                cmd_arg[j++]=cmd+i;
             tag=1;
          }
-         i++;
+       i++;
       }
 
       if(j>=MAX_ARG && i<cmdlen){
-         printf("TOO MANY ARGUMENTS\n");
+         printf("arguments exceed");
          continue;
       }
-      /* cmd_arg NULL Condition. */
+
+
+    for(i=0; *(cmd_arg+i)!=NULL; i++)
+  /*  Identify redirection  */
+ 	if(strcmp(cmd_arg[i],">")==0){
+	redirect_flag=1;
+	*(cmd_arg+i)=NULL;
+	file_name=(cmd_arg[++i]);
+          if(file_name==NULL){
+	     printf("NEKTech_Shell: syntax error near unexpected command\n");
+	     exit(1);
+	}
+     }
+
+   /* cmd_arg NULL Condition. */
       if (cmd_arg[0] == NULL )
          continue;
       /* cmd quit/exit/q: exit NEK Tech Shell */
@@ -71,11 +95,15 @@ main()
       if(strcmp(cmd_arg[0],"cd")==0){
          change_dir(cmd_arg);
          continue;
-      }
-
-      /* other cmd for fork/exec*/
+      } 
+
+
+     /* other cmd for fork/exec*/
+
       run_cmd(cmd_arg);
-   }while(1); 
+	redirect_flag=0;
+  	file_name=NULL;    
+}while(1); 
 }
 
 /* cd - Change Directory