3 files changed, 48 insertions, 2 deletions
diff --git a/tnslc/utils/algo.tnsl b/tnslc/utils/algo.tnsl
index a08c773..73cfb7f 100644
--- a/tnslc/utils/algo.tnsl
+++ b/tnslc/utils/algo.tnsl
@@ -194,7 +194,7 @@
 	return str
 ;/
 
-/; strclone(~uint8 cstr) [~uint8]
+/; strcpy(~uint8 cstr) [~uint8]
 	Vector out
 	out.from_cstr(cstr)
 	return out.as_cstr()
diff --git a/tnslc/utils/c_wrap_linux.tnsl b/tnslc/utils/c_wrap_linux.tnsl
index 814ec1c..1e3155e 100644
--- a/tnslc/utils/c_wrap_linux.tnsl
+++ b/tnslc/utils/c_wrap_linux.tnsl
@@ -1,5 +1,5 @@
 # Must be included at the top of the file
-asm "extern malloc, realloc, free, printf, open, close, read, write"
+asm "extern malloc, realloc, free, printf, open, close, read, write, fseek"
 
 {}uint8 _alert = "Alert!\n\0"
 {}uint8 _dec = "%d\n\0"
@@ -202,6 +202,30 @@ asm "extern malloc, realloc, free, printf, open, close, read, write"
     return out
 ;/
 
+/; _fseek (~void handle, uint pos) [int]
+	int out
+
+	# align stack
+    asm "mov rax, rsp"
+    asm "xor rdx, rdx"
+    asm "mov rcx, 16"
+    asm "div rcx"
+    asm "sub rsp, rdx"
+    # add buffer zone to stack
+	asm "sub rsp, 128"
+
+	# Call c func
+	asm "mov rdi, r10"
+	asm "mov rsi, r11"
+	asm "mov rdx, 0" # standard value for SEEK_SET as per GNU libc
+    asm "call fseek wrt ..plt"
+
+	# get return value
+	asm "mov r12, rax"
+
+	return out
+;/
+
 /; _write_byte (~void handle, ~uint8 byte) [int]
     int out
 
diff --git a/tnslc/utils/file.tnsl b/tnslc/utils/file.tnsl
index 978f31b..22b11f1 100644
--- a/tnslc/utils/file.tnsl
+++ b/tnslc/utils/file.tnsl
@@ -1,6 +1,7 @@
 struct File {
 	Artifact path,
 	~void handle,
+	uint pos,
 	bool at_end
 }
 
@@ -14,6 +15,7 @@ struct File {
 		self.path.split_cstr(str, '/')
 		self.handle = NULL
 		self.at_end = false
+		self.pos = 0
 	;/
 
 	/; relative (~uint8 path) [File]
@@ -75,15 +77,35 @@ struct File {
 	;/
 
 	/; read [uint8]
+		/; if (self.at_end == true)
+			return 0
+		;/
+
 		uint8 out
 		int bytes = _read_byte(self.handle, ~out)
+		self.pos = self.pos + 1
+		
 		/; if (bytes == 0)
 			self.at_end = true
 			return 0
 		;/
+		
 		return out
 	;/
 
+	/; unread
+		/; if (self.pos < 1)
+			return
+		;/
+
+		_fseek(self.handle, self.pos - 1)
+		self.pos = self.pos - 1
+
+		/; if (self.at_end == true)
+			self.at_end = false
+		;/
+	;/
+
 	/; write (uint8 byte)
 		int written = _write_byte(self.handle, ~byte)
 		/; if (written == 0)