diff --git a/.gitignore b/.gitignore
index 23efb9ff..2eb78b11 100644
--- a/.gitignore
+++ b/.gitignore
@@ -108,8 +108,6 @@
 
 /examples/assert
 /examples/cmdline
-/examples/fprintf
-/examples/fprintf_va
 /examples/generic_file
 /examples/generic_malloc
 /examples/generic_mutex
@@ -117,9 +115,11 @@
 /examples/ntoa
 /examples/panic
 /examples/pfa
+/examples/printf_file
+/examples/printf_file_va
 /examples/printf_fmt
-/examples/snprintf
-/examples/snprintf_va
+/examples/printf_str
+/examples/printf_str_va
 /examples/units_human
 
 /tests/multiboot2_header_print1
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index a0f900b8..11caaabc 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -2,16 +2,73 @@ Common
 ------
 
 * Add your name to [COPYING](/COPYING).
-* **Don't** add your name to `AUTHORS` - it's for maintainers.
+* Don't add your name to `AUTHORS` - it's for maintainers.
 * Add copyright notice in the beginning of changed files except the headers.
 * If you change the behavior (even just fix a bug) of **libkernaux** (stable) or
   [libc](/libc), add a record to [ChangeLog](/ChangeLog).
 
+Prohibitions:
+
+* Don't commit binary files
+* Don't commit configuration files of your editor or IDE
+* Don't use encodings other than ASCII and UTF-8
+* Don't use alphabets other than Latin
+* Don't use languages other than English
+* Don't use tabulations (I don't hate tabs, but people can not use them
+  properly)
+* Don't leave trailing whitespaces
+* Don't forget the newline character in the end of files
+
+The following statements are recommendations, but highly encouraged:
+
+* Write documentation
+* Write tests
+* Keep lines less than 80 characters long for better experience on split screen
+
+### Programming mistakes
+
+* Always check documentation, manuals and specifications
+
+Avoid stupid errors with:
+
+* Manual memory management
+  * `malloc` may return `NULL`
+  * Memory leak (forget to `free`)
+  * Use after `free`/`realloc`
+  * Double `free`/`realloc`
+  * `free`ing/`realloc`ating unallocated memory
+  * Changing the original pointer to the allocated memory (use `const`!)
+* `NULL` pointers and `nil`/`None`/whatever objects
+* Division by zero
+* Pointer arithmetic - consider type size
+* Type sizes (like `long` on 32-bit and 64-bit)
+* Integer arithmetic overflow
+* Bit shift
+* Endianness (byte order)
+* Data packing
+* Data alignment
+* Thread safety
+* Undefined behavior
+* Logical expressions (tautology, whatever)
+* Checking for an error (return value, pointer argument, whatever)
+* Use of not fully initialized data
+* Not reading beyond a buffer, array or string
+  * The index of the last item, which is less than the buffer size
+  * Negative indices
+  * The terminating null character in a string
+* Allowed values of arguments
+* Possible values of parameters
+* Operator precedence
+* Default case in switch statements
+* Braces (curly brackets) around code blocks
+
 
 
 C language
 ----------
 
+Use **cppcheck**.
+
 * Name regular functions (*not methods*) and variables in lower snake case
   (example: `foo_bar`).
 * Name macros in upper snake case (example: `FOO_BAR`).
@@ -78,6 +135,22 @@ FooBar_init(foobar);
 FooBar_do_something(foobar);
 ```
 
+* Mark variables and parameters with `const` if you don't plan to modify them
+* Only omit braces (curly brackets) of a block if it's statement is placed on
+  the same line as conditional statement:
+
+```c
+// Good:
+if (foo) return bar;
+if (foo) {
+    return bar;
+}
+
+// Bad:
+if (foo)
+    return bar;
+```
+
 
 
 Python
@@ -90,6 +163,8 @@ Nothing here yet.
 Ruby
 ----
 
+* Freeze objects if you don't plan to modify them
+
 ### Matz's Ruby interpreter
 
 Use **RuboCop**. See [bindings/ruby/.rubocop.yml](/bindings/ruby/.rubocop.yml)
diff --git a/README.md b/README.md
index e2e7124d..d331b46d 100644
--- a/README.md
+++ b/README.md
@@ -48,7 +48,7 @@ zero). Work-in-progress APIs can change at any time.
     * [Declarations](/include/kernaux/arch/)
     * [Functions](/include/kernaux/asm/)
 * Generic types
-  * [File](/include/kernaux/generic/file.h) (*work in progress*)
+  * [File](/include/kernaux/generic/file.h) (*non-breaking since* **?.?.?**)
     * [Example](/examples/generic_file.c)
   * [Memory allocator](/include/kernaux/generic/malloc.h) (*non-breaking since* **?.?.?**)
     * [Example](/examples/generic_malloc.c)
@@ -62,7 +62,7 @@ zero). Work-in-progress APIs can change at any time.
     * [Example](/examples/pfa.c)
 * Data formats
   * [ELF](/include/kernaux/elf.h) (*work in progress*)
-  * [Master Boot Record](/include/kernaux/mbr.h) (*work in progress*)
+  * [MBR](/include/kernaux/mbr.h) (*work in progress*)
   * [Multiboot 2 (GRUB 2)](/include/kernaux/multiboot2.h) (*work in progress*)
 * Utilities
   * [Measurement units utils](/include/kernaux/units.h) (*work in progress*)
@@ -70,17 +70,15 @@ zero). Work-in-progress APIs can change at any time.
   * [Memory map](/include/kernaux/memmap.h.in) (*non-breaking since* **0.4.0**)
     * [Example](/examples/memmap.c)
   * [printf format parser](/include/kernaux/printf_fmt.h) (*work in progress*)
-    * Code from [https://github.com/mpaland/printf](https://github.com/mpaland/printf). Thank you!
     * [Example](/examples/printf_fmt.c)
 * Usual functions
   * [itoa/ftoa replacement](/include/kernaux/ntoa.h) (*non-breaking since* **0.4.0**)
     * [Example](/examples/ntoa.c)
   * [printf replacement](/include/kernaux/printf.h.in) (*non-breaking since* **?.?.?**)
-    * Code from [https://github.com/mpaland/printf](https://github.com/mpaland/printf). Thank you!
-    * [Example: fprintf](/examples/fprintf.c)
-    * [Example: vfprintf](/examples/fprintf_va.c)
-    * [Example: snprintf](/examples/snprintf.c)
-    * [Example: vsnprintf](/examples/snprintf_va.c)
+    * [Example: fprintf](/examples/printf_file.c)
+    * [Example: vfprintf](/examples/printf_file_va.c)
+    * [Example: snprintf](/examples/printf_str.c)
+    * [Example: vsnprintf](/examples/printf_str_va.c)
 * libc replacement (*work in progress*)
   * [ctype.h](/libc/include/ctype.h)
   * [inttypes.h](/libc/include/inttypes.h)
diff --git a/common/printf_orig.yml b/common/printf_orig.yml
index 392da8d9..a1c669c4 100644
--- a/common/printf_orig.yml
+++ b/common/printf_orig.yml
@@ -1,7 +1,7 @@
 # The code was taken from Marco Paland's printf.
 
 # Copyright (c) 2014-2019 Marco Paland <info@paland.com>
-# Copyright (c) 2020-2022 Alex Kotov
+# Copyright (c) 2021-2022 Alex Kotov
 
 # TODO: add remaining tests from
 # https://github.com/mpaland/printf/blob/master/test/test_suite.cpp
diff --git a/configure.ac b/configure.ac
index a0191d86..ee572217 100644
--- a/configure.ac
+++ b/configure.ac
@@ -65,7 +65,7 @@ AC_ARG_WITH(  [asm],          AS_HELP_STRING([--without-asm],          [without
 AC_ARG_WITH(  [cmdline],      AS_HELP_STRING([--without-cmdline],      [without command line parser]))
 AC_ARG_WITH(  [elf],          AS_HELP_STRING([--without-elf],          [without ELF utils]))
 AC_ARG_WITH(  [free-list],    AS_HELP_STRING([--without-free-list],    [without free list memory allocator]))
-AC_ARG_WITH(  [mbr],          AS_HELP_STRING([--without-mbr],          [without Master Boot Record]))
+AC_ARG_WITH(  [mbr],          AS_HELP_STRING([--without-mbr],          [without MBR utils]))
 AC_ARG_WITH(  [memmap],       AS_HELP_STRING([--without-memmap],       [without memory map]))
 AC_ARG_WITH(  [multiboot2],   AS_HELP_STRING([--without-multiboot2],   [without Multiboot 2 information parser]))
 AC_ARG_WITH(  [ntoa],         AS_HELP_STRING([--without-ntoa],         [without itoa/ftoa]))
@@ -248,7 +248,7 @@ AS_IF([test "$with_asm"            = yes], [AC_DEFINE([WITH_ASM],            [1]
 AS_IF([test "$with_cmdline"        = yes], [AC_DEFINE([WITH_CMDLINE],        [1], [with command line parser])])
 AS_IF([test "$with_elf"            = yes], [AC_DEFINE([WITH_ELF],            [1], [with ELF utils])])
 AS_IF([test "$with_free_list"      = yes], [AC_DEFINE([WITH_FREE_LIST],      [1], [with free list memory allocator])])
-AS_IF([test "$with_mbr"            = yes], [AC_DEFINE([WITH_MBR],            [1], [with Master Boot Record])])
+AS_IF([test "$with_mbr"            = yes], [AC_DEFINE([WITH_MBR],            [1], [with MBR utils])])
 AS_IF([test "$with_memmap"         = yes], [AC_DEFINE([WITH_MEMMAP],         [1], [with memory map])])
 AS_IF([test "$with_multiboot2"     = yes], [AC_DEFINE([WITH_MULTIBOOT2],     [1], [with Multiboot 2 information parser])])
 AS_IF([test "$with_ntoa"           = yes], [AC_DEFINE([WITH_NTOA],           [1], [with ntoa])])
diff --git a/examples/Makefile.am b/examples/Makefile.am
index 3e699b38..3d4ce958 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -21,26 +21,6 @@ cmdline_LDADD = $(top_builddir)/libkernaux.la
 cmdline_SOURCES = main.c cmdline.c
 endif
 
-###########
-# fprintf #
-###########
-
-if WITH_PRINTF
-TESTS += fprintf
-fprintf_LDADD = $(top_builddir)/libkernaux.la
-fprintf_SOURCES = main.c fprintf.c
-endif
-
-##############
-# fprintf_va #
-##############
-
-if WITH_PRINTF
-TESTS += fprintf_va
-fprintf_va_LDADD = $(top_builddir)/libkernaux.la
-fprintf_va_SOURCES = main.c fprintf_va.c
-endif
-
 ################
 # generic_file #
 ################
@@ -103,6 +83,26 @@ pfa_LDADD = $(top_builddir)/libkernaux.la
 pfa_SOURCES = main.c pfa.c
 endif
 
+###############
+# printf_file #
+###############
+
+if WITH_PRINTF
+TESTS += printf_file
+printf_file_LDADD = $(top_builddir)/libkernaux.la
+printf_file_SOURCES = main.c printf_file.c
+endif
+
+##################
+# printf_file_va #
+##################
+
+if WITH_PRINTF
+TESTS += printf_file_va
+printf_file_va_LDADD = $(top_builddir)/libkernaux.la
+printf_file_va_SOURCES = main.c printf_file_va.c
+endif
+
 ##############
 # printf_fmt #
 ##############
@@ -113,24 +113,24 @@ printf_fmt_LDADD = $(top_builddir)/libkernaux.la
 printf_fmt_SOURCES = main.c printf_fmt.c
 endif
 
-############
-# snprintf #
-############
+##############
+# printf_str #
+##############
 
 if WITH_PRINTF
-TESTS += snprintf
-snprintf_LDADD = $(top_builddir)/libkernaux.la
-snprintf_SOURCES = main.c snprintf.c
+TESTS += printf_str
+printf_str_LDADD = $(top_builddir)/libkernaux.la
+printf_str_SOURCES = main.c printf_str.c
 endif
 
-###############
-# snprintf_va #
-###############
+#################
+# printf_str_va #
+#################
 
 if WITH_PRINTF
-TESTS += snprintf_va
-snprintf_va_LDADD = $(top_builddir)/libkernaux.la
-snprintf_va_SOURCES = main.c snprintf_va.c
+TESTS += printf_str_va
+printf_str_va_LDADD = $(top_builddir)/libkernaux.la
+printf_str_va_SOURCES = main.c printf_str_va.c
 endif
 
 ###############
diff --git a/examples/fprintf.c b/examples/printf_file.c
similarity index 100%
rename from examples/fprintf.c
rename to examples/printf_file.c
diff --git a/examples/fprintf_va.c b/examples/printf_file_va.c
similarity index 100%
rename from examples/fprintf_va.c
rename to examples/printf_file_va.c
diff --git a/examples/snprintf.c b/examples/printf_str.c
similarity index 100%
rename from examples/snprintf.c
rename to examples/printf_str.c
diff --git a/examples/snprintf_va.c b/examples/printf_str_va.c
similarity index 100%
rename from examples/snprintf_va.c
rename to examples/printf_str_va.c
diff --git a/include/kernaux/arch/i386.h b/include/kernaux/arch/i386.h
index ba9bf4e2..0a8a3ce5 100644
--- a/include/kernaux/arch/i386.h
+++ b/include/kernaux/arch/i386.h
@@ -82,48 +82,48 @@ KERNAUX_STATIC_TEST_STRUCT_SIZE(KernAux_Arch_I386_DTE, 8);
  */
 struct KernAux_Arch_I386_TSS {
     // 0x00
-    unsigned prev_tss    : 16;
-    unsigned _zero0      : 16;
+    uint16_t prev_tss;
+    uint16_t _zero0;
     // 0x04
-    unsigned esp0        : 32;
-    unsigned ss0         : 16;
-    unsigned _zero1      : 16;
-    unsigned esp1        : 32;
-    unsigned ss1         : 16;
-    unsigned _zero2      : 16;
-    unsigned esp2        : 32;
-    unsigned ss2         : 16;
-    unsigned _zero3      : 16;
+    uint32_t esp0;
+    uint16_t ss0;
+    uint16_t _zero1;
+    uint32_t esp1;
+    uint16_t ss1;
+    uint16_t _zero2;
+    uint32_t esp2;
+    uint16_t ss2;
+    uint16_t _zero3;
     // 0x1c
-    unsigned cr3         : 32;
-    unsigned eip         : 32;
-    unsigned eflags      : 32;
-    unsigned eax         : 32;
-    unsigned ecx         : 32;
-    unsigned edx         : 32;
-    unsigned ebx         : 32;
-    unsigned esp         : 32;
-    unsigned ebp         : 32;
-    unsigned esi         : 32;
-    unsigned edi         : 32;
+    uint32_t cr3;
+    uint32_t eip;
+    uint32_t eflags;
+    uint32_t eax;
+    uint32_t ecx;
+    uint32_t edx;
+    uint32_t ebx;
+    uint32_t esp;
+    uint32_t ebp;
+    uint32_t esi;
+    uint32_t edi;
     // 0x48
-    unsigned es          : 16;
-    unsigned _zero4      : 16;
-    unsigned cs          : 16;
-    unsigned _zero5      : 16;
-    unsigned ss          : 16;
-    unsigned _zero6      : 16;
-    unsigned ds          : 16;
-    unsigned _zero7      : 16;
-    unsigned fs          : 16;
-    unsigned _zero8      : 16;
-    unsigned gs          : 16;
-    unsigned _zero9      : 16;
-    unsigned ldt         : 16;
-    unsigned _zero10     : 16;
+    uint16_t es;
+    uint16_t _zero4;
+    uint16_t cs;
+    uint16_t _zero5;
+    uint16_t ss;
+    uint16_t _zero6;
+    uint16_t ds;
+    uint16_t _zero7;
+    uint16_t fs;
+    uint16_t _zero8;
+    uint16_t gs;
+    uint16_t _zero9;
+    uint16_t ldt;
+    uint16_t _zero10;
     // 0x64
-    unsigned _zero11     : 16;
-    unsigned io_map_base : 16;
+    uint16_t _zero11;
+    uint16_t io_map_base;
 }
 KERNAUX_PACKING_ATTR;
 
diff --git a/libc/src/asm/i386/longjmp.S b/libc/src/asm/i386/longjmp.S
index f0439e29..00fafbdb 100644
--- a/libc/src/asm/i386/longjmp.S
+++ b/libc/src/asm/i386/longjmp.S
@@ -1,9 +1,9 @@
 /**
  * The code was taken from musl libc.
  *
- * Copyright (c) 2011      Rich Felker
- * Copyright (c) 2020-2022 Alex Kotov
- * Copyright (c) 2022      Alexander Monakov
+ * Copyright (c) 2011 Rich Felker
+ * Copyright (c) 2022 Alexander Monakov
+ * Copyright (c) 2022 Alex Kotov
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/libc/src/asm/i386/setjmp.S b/libc/src/asm/i386/setjmp.S
index 210b1716..841544d7 100644
--- a/libc/src/asm/i386/setjmp.S
+++ b/libc/src/asm/i386/setjmp.S
@@ -2,7 +2,7 @@
  * The code was taken from musl libc.
  *
  * Copyright (c) 2011-2015 Rich Felker
- * Copyright (c) 2020-2022 Alex Kotov
+ * Copyright (c) 2022      Alex Kotov
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/libc/src/asm/x86_64/longjmp.S b/libc/src/asm/x86_64/longjmp.S
index d978945a..7565082b 100644
--- a/libc/src/asm/x86_64/longjmp.S
+++ b/libc/src/asm/x86_64/longjmp.S
@@ -3,8 +3,8 @@
  *
  * Copyright (c) 2011      Nicholas J. Kain
  * Copyright (c) 2011-2012 Rich Felker
- * Copyright (c) 2020-2022 Alex Kotov
  * Copyright (c) 2022      Alexander Monakov
+ * Copyright (c) 2022      Alex Kotov
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/libc/src/asm/x86_64/setjmp.S b/libc/src/asm/x86_64/setjmp.S
index 6a565352..6279a60d 100644
--- a/libc/src/asm/x86_64/setjmp.S
+++ b/libc/src/asm/x86_64/setjmp.S
@@ -3,8 +3,8 @@
  *
  * Copyright (c) 2011      Nicholas J. Kain
  * Copyright (c) 2011-2012 Rich Felker
- * Copyright (c) 2020-2022 Alex Kotov
  * Copyright (c) 2022      Alexander Monakov
+ * Copyright (c) 2022      Alex Kotov
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/src/free_list.c b/src/free_list.c
index 88a9ee01..38f58c58 100644
--- a/src/free_list.c
+++ b/src/free_list.c
@@ -2,7 +2,7 @@
  * The code was inspired by the Embedded Artistry's libmemory.
  *
  * Copyright (c) 2017-2022 Embedded Artistry LLC
- * Copyright (c) 2020-2022 Alex Kotov
+ * Copyright (c) 2022      Alex Kotov
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/src/printf.c b/src/printf.c
index cc822a35..58295486 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -2,7 +2,7 @@
  * The code was taken from Marco Paland's printf.
  *
  * Copyright (c) 2014-2019 Marco Paland <info@paland.com>
- * Copyright (c) 2020-2022 Alex Kotov
+ * Copyright (c) 2021-2022 Alex Kotov
  *
  * Tiny [v]fprintf, sfprintf and [v]snprintf implementation, optimized for speed
  * on embedded systems with a very limited resources. These routines are thread
diff --git a/src/printf_fmt.c b/src/printf_fmt.c
index 60746da2..43dbf666 100644
--- a/src/printf_fmt.c
+++ b/src/printf_fmt.c
@@ -2,7 +2,7 @@
  * The code was taken from Marco Paland's printf.
  *
  * Copyright (c) 2014-2019 Marco Paland <info@paland.com>
- * Copyright (c) 2020-2022 Alex Kotov
+ * Copyright (c) 2021-2022 Alex Kotov
  */
 
 #ifdef HAVE_CONFIG_H