--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/usr/user.h	Sun Feb 04 17:54:49 2018 +0900
@@ -0,0 +1,38 @@
+struct stat;
+
+// system calls
+int fork(void);
+int exit(void) __attribute__((noreturn));
+int wait(void);
+int pipe(int*);
+int write(int, void*, int);
+int read(int, void*, int);
+int close(int);
+int kill(int);
+int exec(char*, char**);
+int open(char*, int);
+int mknod(char*, short, short);
+int unlink(char*);
+int fstat(int fd, struct stat*);
+int link(char*, char*);
+int mkdir(char*);
+int chdir(char*);
+int dup(int);
+int getpid(void);
+char* sbrk(int);
+int sleep(int);
+int uptime(void);
+
+// ulib.c
+int stat(char*, struct stat*);
+char* strcpy(char*, char*);
+void *memmove(void*, void*, int);
+char* strchr(const char*, char c);
+int strcmp(const char*, const char*);
+void printf(int, char*, ...);
+char* gets(char*, int max);
+uint strlen(char*);
+void* memset(void*, int, uint);
+void* malloc(uint);
+void free(void*);
+int atoi(const char*);