diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }
diff --git a/src/kernel/stringmap/stringmapSyscalls.c b/src/kernel/stringmap/stringmapSyscalls.c
index 9ee8c6f..33e3d4e 100644
--- a/src/kernel/stringmap/stringmapSyscalls.c
+++ b/src/kernel/stringmap/stringmapSyscalls.c
@@ -29,3 +29,8 @@
     memcpy(string, buffer, size + 1);
     unmapPage(buffer);
 }
+
+void handleDiscardStringSyscall(Syscall *call) {
+    uintptr_t stringId = call->parameters[0];
+    discardString(stringId);
+}

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }
diff --git a/src/kernel/stringmap/stringmapSyscalls.c b/src/kernel/stringmap/stringmapSyscalls.c
index 9ee8c6f..33e3d4e 100644
--- a/src/kernel/stringmap/stringmapSyscalls.c
+++ b/src/kernel/stringmap/stringmapSyscalls.c
@@ -29,3 +29,8 @@
     memcpy(string, buffer, size + 1);
     unmapPage(buffer);
 }
+
+void handleDiscardStringSyscall(Syscall *call) {
+    uintptr_t stringId = call->parameters[0];
+    discardString(stringId);
+}
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index f1cb269..abe9808 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -57,7 +57,7 @@
     handleFireEventSyscall, handleSubscribeEventSyscall;
 extern uintptr_t handleSubscribeInterruptSyscall;
 extern uintptr_t handleInsertStringSyscall, handleReadStringLengthSyscall,
-    handleReadStringSyscall;
+    handleReadStringSyscall, handleDiscardStringSyscall;
 
 void (*syscallHandlers[])(Syscall *) = {
     0,
@@ -77,6 +77,7 @@
     (void *)&handleInsertStringSyscall,
     (void *)&handleReadStringLengthSyscall,
     (void *)&handleReadStringSyscall,
+    (void *)&handleDiscardStringSyscall,
 };
 
 void processSyscall(Syscall *call) {

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }
diff --git a/src/kernel/stringmap/stringmapSyscalls.c b/src/kernel/stringmap/stringmapSyscalls.c
index 9ee8c6f..33e3d4e 100644
--- a/src/kernel/stringmap/stringmapSyscalls.c
+++ b/src/kernel/stringmap/stringmapSyscalls.c
@@ -29,3 +29,8 @@
     memcpy(string, buffer, size + 1);
     unmapPage(buffer);
 }
+
+void handleDiscardStringSyscall(Syscall *call) {
+    uintptr_t stringId = call->parameters[0];
+    discardString(stringId);
+}
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index f1cb269..abe9808 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -57,7 +57,7 @@
     handleFireEventSyscall, handleSubscribeEventSyscall;
 extern uintptr_t handleSubscribeInterruptSyscall;
 extern uintptr_t handleInsertStringSyscall, handleReadStringLengthSyscall,
-    handleReadStringSyscall;
+    handleReadStringSyscall, handleDiscardStringSyscall;
 
 void (*syscallHandlers[])(Syscall *) = {
     0,
@@ -77,6 +77,7 @@
     (void *)&handleInsertStringSyscall,
     (void *)&handleReadStringLengthSyscall,
     (void *)&handleReadStringSyscall,
+    (void *)&handleDiscardStringSyscall,
 };
 
 void processSyscall(Syscall *call) {
diff --git a/src/kernel/util/strings.c b/src/kernel/util/strings.c
index b023bcb..324a58e 100644
--- a/src/kernel/util/strings.c
+++ b/src/kernel/util/strings.c
@@ -13,6 +13,9 @@
 }
 
 uint32_t strlen(char *string) {
+    if (!string) {
+        return 0;
+    }
     uint32_t size = 0;
     while (*string) {
         string++;

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }
diff --git a/src/kernel/stringmap/stringmapSyscalls.c b/src/kernel/stringmap/stringmapSyscalls.c
index 9ee8c6f..33e3d4e 100644
--- a/src/kernel/stringmap/stringmapSyscalls.c
+++ b/src/kernel/stringmap/stringmapSyscalls.c
@@ -29,3 +29,8 @@
     memcpy(string, buffer, size + 1);
     unmapPage(buffer);
 }
+
+void handleDiscardStringSyscall(Syscall *call) {
+    uintptr_t stringId = call->parameters[0];
+    discardString(stringId);
+}
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index f1cb269..abe9808 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -57,7 +57,7 @@
     handleFireEventSyscall, handleSubscribeEventSyscall;
 extern uintptr_t handleSubscribeInterruptSyscall;
 extern uintptr_t handleInsertStringSyscall, handleReadStringLengthSyscall,
-    handleReadStringSyscall;
+    handleReadStringSyscall, handleDiscardStringSyscall;
 
 void (*syscallHandlers[])(Syscall *) = {
     0,
@@ -77,6 +77,7 @@
     (void *)&handleInsertStringSyscall,
     (void *)&handleReadStringLengthSyscall,
     (void *)&handleReadStringSyscall,
+    (void *)&handleDiscardStringSyscall,
 };
 
 void processSyscall(Syscall *call) {
diff --git a/src/kernel/util/strings.c b/src/kernel/util/strings.c
index b023bcb..324a58e 100644
--- a/src/kernel/util/strings.c
+++ b/src/kernel/util/strings.c
@@ -13,6 +13,9 @@
 }
 
 uint32_t strlen(char *string) {
+    if (!string) {
+        return 0;
+    }
     uint32_t size = 0;
     while (*string) {
         string++;
diff --git a/src/userland/hlib/include/syscalls.h b/src/userland/hlib/include/syscalls.h
index 07251c3..dc85e4b 100644
--- a/src/userland/hlib/include/syscalls.h
+++ b/src/userland/hlib/include/syscalls.h
@@ -22,6 +22,7 @@
     SYS_INSERT_STRING = 14,
     SYS_GET_STRING_LENGTH = 15,
     SYS_READ_STRING = 16,
+    SYS_DISCARD_STRING = 17,
 } SyscallIds;
 
 #endif

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }
diff --git a/src/kernel/stringmap/stringmapSyscalls.c b/src/kernel/stringmap/stringmapSyscalls.c
index 9ee8c6f..33e3d4e 100644
--- a/src/kernel/stringmap/stringmapSyscalls.c
+++ b/src/kernel/stringmap/stringmapSyscalls.c
@@ -29,3 +29,8 @@
     memcpy(string, buffer, size + 1);
     unmapPage(buffer);
 }
+
+void handleDiscardStringSyscall(Syscall *call) {
+    uintptr_t stringId = call->parameters[0];
+    discardString(stringId);
+}
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index f1cb269..abe9808 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -57,7 +57,7 @@
     handleFireEventSyscall, handleSubscribeEventSyscall;
 extern uintptr_t handleSubscribeInterruptSyscall;
 extern uintptr_t handleInsertStringSyscall, handleReadStringLengthSyscall,
-    handleReadStringSyscall;
+    handleReadStringSyscall, handleDiscardStringSyscall;
 
 void (*syscallHandlers[])(Syscall *) = {
     0,
@@ -77,6 +77,7 @@
     (void *)&handleInsertStringSyscall,
     (void *)&handleReadStringLengthSyscall,
     (void *)&handleReadStringSyscall,
+    (void *)&handleDiscardStringSyscall,
 };
 
 void processSyscall(Syscall *call) {
diff --git a/src/kernel/util/strings.c b/src/kernel/util/strings.c
index b023bcb..324a58e 100644
--- a/src/kernel/util/strings.c
+++ b/src/kernel/util/strings.c
@@ -13,6 +13,9 @@
 }
 
 uint32_t strlen(char *string) {
+    if (!string) {
+        return 0;
+    }
     uint32_t size = 0;
     while (*string) {
         string++;
diff --git a/src/userland/hlib/include/syscalls.h b/src/userland/hlib/include/syscalls.h
index 07251c3..dc85e4b 100644
--- a/src/userland/hlib/include/syscalls.h
+++ b/src/userland/hlib/include/syscalls.h
@@ -22,6 +22,7 @@
     SYS_INSERT_STRING = 14,
     SYS_GET_STRING_LENGTH = 15,
     SYS_READ_STRING = 16,
+    SYS_DISCARD_STRING = 17,
 } SyscallIds;
 
 #endif
diff --git a/src/userland/hlib/main.c b/src/userland/hlib/main.c
index 6734cdc..f11ba62 100644
--- a/src/userland/hlib/main.c
+++ b/src/userland/hlib/main.c
@@ -94,3 +94,7 @@
 void readString(uintptr_t stringId, void *buffer) {
     syscall(SYS_READ_STRING, stringId, U32(buffer), 0, 0);
 }
+
+void discardString(uintptr_t stringId) {
+    syscall(SYS_DISCARD_STRING, stringId, 0, 0, 0);
+}

diff --git a/src/include/hlib.h b/src/include/hlib.h
index 1e94acb..d36b727 100644
--- a/src/include/hlib.h
+++ b/src/include/hlib.h
@@ -32,5 +32,6 @@
 extern uintptr_t insertString(char *string, uintptr_t size);
 extern uintptr_t getStringLength(uintptr_t stringId);
 extern void readString(uintptr_t stringId, void *buffer);
+extern void discardString(uintptr_t stringId);
 
 #endif
diff --git a/src/kernel/stringmap/stringmap.c b/src/kernel/stringmap/stringmap.c
index 6e0cea1..44a287f 100644
--- a/src/kernel/stringmap/stringmap.c
+++ b/src/kernel/stringmap/stringmap.c
@@ -47,13 +47,13 @@
 
 void discardString(uintptr_t stringId) {
     MapLayer currentLayer = rootLayer;
-    for (uint32_t startBit = 0; startBit < sizeof(uintptr_t) - 4;
-         startBit += 4) {
+    for (uint32_t startBit = 0; startBit < BITS(uintptr_t) - 4; startBit += 4) {
         void *nextLayer = currentLayer[(stringId >> startBit) & 0xF];
         if (!nextLayer) {
             return;
         }
         currentLayer = nextLayer;
     }
-    currentLayer[stringId >> (sizeof(uintptr_t) - 4)] = NULL;
+    free(currentLayer[stringId >> (BITS(uintptr_t) - 4)]);
+    currentLayer[stringId >> (BITS(uintptr_t) - 4)] = NULL;
 }
diff --git a/src/kernel/stringmap/stringmapSyscalls.c b/src/kernel/stringmap/stringmapSyscalls.c
index 9ee8c6f..33e3d4e 100644
--- a/src/kernel/stringmap/stringmapSyscalls.c
+++ b/src/kernel/stringmap/stringmapSyscalls.c
@@ -29,3 +29,8 @@
     memcpy(string, buffer, size + 1);
     unmapPage(buffer);
 }
+
+void handleDiscardStringSyscall(Syscall *call) {
+    uintptr_t stringId = call->parameters[0];
+    discardString(stringId);
+}
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index f1cb269..abe9808 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -57,7 +57,7 @@
     handleFireEventSyscall, handleSubscribeEventSyscall;
 extern uintptr_t handleSubscribeInterruptSyscall;
 extern uintptr_t handleInsertStringSyscall, handleReadStringLengthSyscall,
-    handleReadStringSyscall;
+    handleReadStringSyscall, handleDiscardStringSyscall;
 
 void (*syscallHandlers[])(Syscall *) = {
     0,
@@ -77,6 +77,7 @@
     (void *)&handleInsertStringSyscall,
     (void *)&handleReadStringLengthSyscall,
     (void *)&handleReadStringSyscall,
+    (void *)&handleDiscardStringSyscall,
 };
 
 void processSyscall(Syscall *call) {
diff --git a/src/kernel/util/strings.c b/src/kernel/util/strings.c
index b023bcb..324a58e 100644
--- a/src/kernel/util/strings.c
+++ b/src/kernel/util/strings.c
@@ -13,6 +13,9 @@
 }
 
 uint32_t strlen(char *string) {
+    if (!string) {
+        return 0;
+    }
     uint32_t size = 0;
     while (*string) {
         string++;
diff --git a/src/userland/hlib/include/syscalls.h b/src/userland/hlib/include/syscalls.h
index 07251c3..dc85e4b 100644
--- a/src/userland/hlib/include/syscalls.h
+++ b/src/userland/hlib/include/syscalls.h
@@ -22,6 +22,7 @@
     SYS_INSERT_STRING = 14,
     SYS_GET_STRING_LENGTH = 15,
     SYS_READ_STRING = 16,
+    SYS_DISCARD_STRING = 17,
 } SyscallIds;
 
 #endif
diff --git a/src/userland/hlib/main.c b/src/userland/hlib/main.c
index 6734cdc..f11ba62 100644
--- a/src/userland/hlib/main.c
+++ b/src/userland/hlib/main.c
@@ -94,3 +94,7 @@
 void readString(uintptr_t stringId, void *buffer) {
     syscall(SYS_READ_STRING, stringId, U32(buffer), 0, 0);
 }
+
+void discardString(uintptr_t stringId) {
+    syscall(SYS_DISCARD_STRING, stringId, 0, 0, 0);
+}
diff --git a/src/userland/loader/main.c b/src/userland/loader/main.c
index 54e9a72..cdef5a7 100644
--- a/src/userland/loader/main.c
+++ b/src/userland/loader/main.c
@@ -19,5 +19,9 @@
     log(lengthString);
     readString(id, readBuffer);
     log(readBuffer);
+    discardString(id);
+    length = getStringLength(id);
+    lengthString[0] = '0' + length;
+    log(lengthString);
     return 0;
 }