+int strcmp(const char *s1, const char *s2)
+{
+ while(*s1 && *s1 == *s2) {
+ s1++;
+ s2++;
+ }
+ return *s1 - *s2;
+}
+
+int strcasecmp(const char *s1, const char *s2)
+{
+ while(*s1 && tolower(*s1) == tolower(*s2)) {
+ s1++;
+ s2++;
+ }
+ return tolower(*s1) - tolower(*s2);
+}
+
+int strncmp(const char *s1, const char *s2, int n)
+{
+ if(n <= 0) return 0;
+
+ while(n-- > 0 && *s1 && *s2 && *s1 == *s2) {
+ s1++;
+ s2++;
+ }
+
+ if(n <= 0) return 0;
+ return *s1 - *s2;
+}
+
+int strncasecmp(const char *s1, const char *s2, int n)
+{
+ if(n <= 0) return 0;
+
+ while(n-- > 0 && *s1 && *s2 && tolower(*s1) == tolower(*s2)) {
+ s1++;
+ s2++;
+ }
+
+ if(n <= 0) return 0;
+ return tolower(*s1) - tolower(*s2);
+}
+
+char *strcpy(char *dest, const char *src)
+{
+ char *dptr = dest;
+ while((*dptr++ = *src++));
+ return dest;
+}
+
+char *strcat(char *dest, const char *src)
+{
+ strcpy(dest + strlen(dest), src);
+ return dest;
+}
+
+char *strncpy(char *dest, const char *src, int n)
+{
+ char *dptr = dest;
+ while(n-- > 0 && (*dptr++ = *src++));
+ return dest;
+}
+
+
+static const char *errstr[] = {
+ "Success",
+ "Foo",
+ "Interrupted",
+ "Invalid",
+ "Child",
+ "Timeout",
+ "Out of memory",
+ "I/O error",
+ "Not found",
+ "Name too long",
+ "No space left on device",
+ "Permission denied",
+ "Not a directory",
+ "Is a directory",
+ "Does not exist",
+ 0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,
+ 0,0,0,0,0,0,0,
+ "Bug"
+};
+
+char *strerror(int err)
+{
+ if(err < 0 || err > sizeof errstr / sizeof *errstr || !errstr[err]) {
+ return "Unknown";
+ }
+ return (char*)errstr[err];