shlib.h

// Shell.

#include "types.h"
#include "user.h"
#include "fcntl.h"
#include "stat.h"
#include "fs.h"

// Parsed command representation
#define EXEC  1
#define REDIR 2
#define PIPE  3
#define LIST  4
#define BACK  5

#define MAXARGS 10

struct cmd {
  int type;
};

struct execcmd {
  int type;
  char *argv[MAXARGS];
  char *eargv[MAXARGS];
};

struct redircmd {
  int type;
  struct cmd *cmd;
  char *file;
  char *efile;
  int mode;
  int fd;
};

struct pipecmd {
  int type;
  struct cmd *left;
  struct cmd *right;
};

struct listcmd {
  int type;
  struct cmd *left;
  struct cmd *right;
};

struct backcmd {
  int type;
  struct cmd *cmd;
};

int fork1(void);  // Fork but panics on failure.
void panic(char*);
struct cmd *parsecmd(char*);

// Execute cmd.  Never returns.
void runcmd(struct cmd *cmd);

int getcmd(char *buf, int nbuf);

int strprefix(char *str ,char *pre);

char* strimAndTrip(char* a);

void shparsedollar(char* nbuf, char* buf);