syscalls: implement sysctl and add process listing

kernel-src/include/string.h

@@ -6,6 +6,7 @@
 size_t strlen(const char *str);
 size_t strnlen(const char *str, size_t max);
 char *strcpy(char *dest, const char *src);
+char *strncpy(char *dest, const char *src, size_t n);
 char *strcat(char *dest, const char *str);
 void *memcpy(void *dest, const void *src, size_t size);
 void *memset(void *dest, int what, size_t size);
@@ -15,5 +16,6 @@ int memcmp(const void *a, const void *b, size_t s);
 void *memmove(void *_d, const void *_s, size_t c);
 char *strerror(int errno);
 long long atoll(const char *c);
+char *strrchr(const char *s, char c);
 
 #endif