diff --git a/Os/Posix/test/ut/PosixFileTests.cpp b/Os/Posix/test/ut/PosixFileTests.cpp
index d75c5bc40f..55cc7dfc11 100644
--- a/Os/Posix/test/ut/PosixFileTests.cpp
+++ b/Os/Posix/test/ut/PosixFileTests.cpp
@@ -33,8 +33,8 @@ bool check_permissions(const char* path, int permission) {
 //!
 std::shared_ptr<std::string> get_test_filename(bool random) {
     const char* filename = TEST_FILE;
-    char full_buffer[PATH_MAX];
-    char buffer[PATH_MAX - sizeof(BASE_PATH)];
+    char full_buffer[_POSIX_PATH_MAX];
+    char buffer[_POSIX_PATH_MAX - sizeof(BASE_PATH)];
     // When random, select random characters
     if (random) {
         filename = buffer;
@@ -47,7 +47,7 @@ std::shared_ptr<std::string> get_test_filename(bool random) {
         }
         buffer[i] = 0; // Terminate random string
     }
-    (void) snprintf(full_buffer, PATH_MAX, "%s/%s", BASE_PATH, filename);
+    (void) snprintf(full_buffer, _POSIX_PATH_MAX, "%s/%s", BASE_PATH, filename);
     // Create a shared pointer wrapping our filename buffer
     std::shared_ptr<std::string> pointer(new std::string(full_buffer), std::default_delete<std::string>());
     return pointer;
diff --git a/Os/test/ut/file/FileRules.cpp b/Os/test/ut/file/FileRules.cpp
index e708ec9569..39b0399b61 100644
--- a/Os/test/ut/file/FileRules.cpp
+++ b/Os/test/ut/file/FileRules.cpp
@@ -231,7 +231,7 @@ void Os::Test::File::Tester::assert_file_seek(const FwSignedSizeType original_po
     ASSERT_EQ(this->m_shadow.position(shadow_position), Os::File::Status::OP_OK);
 
     const FwSignedSizeType expected_offset = (absolute) ? seek_desired : (original_position + seek_desired);
-    if (expected_offset > 0) {
+    if (expected_offset >= 0) {
         ASSERT_EQ(new_position, expected_offset);
     } else {
         ASSERT_EQ(new_position, original_position);
@@ -497,7 +497,7 @@ void Os::Test::File::Tester::Preallocate::action(
     state.assert_file_consistent();
     FileState original_file_state = state.current_file_state();
     FwSignedSizeType offset = static_cast<FwSignedSizeType>(STest::Pick::lowerUpper(0, FILE_DATA_MAXIMUM));
-    FwSignedSizeType length = static_cast<FwSignedSizeType>(STest::Pick::lowerUpper(0, FILE_DATA_MAXIMUM));
+    FwSignedSizeType length = static_cast<FwSignedSizeType>(STest::Pick::lowerUpper(1, FILE_DATA_MAXIMUM));
     Os::File::Status status = state.m_file.preallocate(offset, length);
     ASSERT_EQ(Os::File::Status::OP_OK, status);
     state.shadow_preallocate(offset, length);
diff --git a/Os/test/ut/file/SyntheticFileSystem.cpp b/Os/test/ut/file/SyntheticFileSystem.cpp
index b81f7c6eae..5bcb59cbf4 100644
--- a/Os/test/ut/file/SyntheticFileSystem.cpp
+++ b/Os/test/ut/file/SyntheticFileSystem.cpp
@@ -191,7 +191,7 @@ Os::File::Status SyntheticFile::seek(const FwSignedSizeType offset, const SeekTy
         status = Os::File::Status::NOT_OPENED;
     } else {
         FwSignedSizeType new_offset = (absolute) ? offset : (offset + this->m_data->m_pointer);
-        if (new_offset > 0) {
+        if (new_offset >= 0) {
             this->m_data->m_pointer = new_offset;
         } else {
             status = Os::File::Status::INVALID_ARGUMENT;