/* redirects the output of ipcs to grep "<user name>" redirected
	to "ipc.dat"(temporary) file
   Then, redirects output of whoami to whoami.dat (temp file).
   the ipc.dat file is read and contents analyzed and
   a commandline for ipcsrm is prepared
   and then a system call to ipcsrm is done
*/


#include <stdio.h>

char str[300];
char line[300];
char cline[300];
char dline[300];
FILE *fin;
int i;

main(int argc, char *argv[])
{system("whoami > whoami.dat");
  fin = fopen("whoami.dat","r");
  fscanf(fin,"%s\n",dline);
  fclose(fin);
  unlink("whoami.dat");
  sprintf( str, "ipcs |grep %s >ipc.dat",dline);
  system( str );
  fin = fopen("ipc.dat", "r");
  if (fin==NULL)
    {
      printf("Error in ipcs piping \n");
      exit(0);
    }
  strcpy(cline, "ipcrm");
  i=0;
  while( !feof(fin))
    {
      i++;
      fscanf(fin, "%s\n", line ); /* m or s */
      if (feof(fin)) break;
      strcat(cline, " -");
      strcat( cline, line );
      fscanf( fin, "%s\n", line ); /* shmid, semid */
      strcat( cline, " ");
      strcat( cline, line );
      fscanf( fin, "%s\n", line);   /* uid / key */
      fscanf( fin, "%s", line ); /* mode */
      fscanf( fin, "%s", line ); /* owner */
      fscanf( fin, "%s", line ); /* group */
    }
  if (i==1)
    {
      printf("No IPC resources present for user %s\n",dline);
      unlink("ipc.dat");
      exit(0);
    }
  printf("\n Calling :  %s \n", cline );
  system( cline );
  unlink("ipc.dat");
}