README.md

   1 A collection of portable, strict C99, single-header implementations of common libc extensions.
   2
   3 All functions are implemented as macros expanding to an internal function reference, this allows to use the headers with no meta build system - it compiles even if the extensions are already present, see _How to_ on disabling this behaviour.
   4
   5 ### How to
   6
   7 Include the header in every file needed as usual:
   8
   9 ```
  10 #include "<ext-func-name>.h"
  11 ```
  12
  13 In the file chosen for the function implementation:
  14
  15 ```
  16 #define <EXT-FUNC-NAME>_IMPLEMENTATION
  17 #include "<ext-func-name.h>"
  18 ```
  19
  20 By default, the header won't have any stdlib includes, change that with:
  21
  22 ```
  23 #define <EXT-FUNC-NAME>_INCLUDE_LIBC
  24 ```
  25
  26 Or disable function, type and variable override with:
  27
  28 ```
  29 #define HAVE_<EXT-FUNC-NAME>
  30 ```
  31
  32 ### Specifics
  33
  34 ---
  35
  36 ### asprintf
  37
  38 includes `vasprintf()` and `asprintf()`
  39
  40 ---
  41
  42 ### fgetln
  43
  44 includes `fgetln()`
  45
  46 ---
  47
  48 ### getopt\_long
  49
  50 includes `getopt()`, `getsubopt()`, `getopt_long()` and `getopt_long_only()`
  51
  52 `getopt_long.h` has additional macros related to argument
  53 permuting, defining those enables it per function (GNU behaviour, can still be disabled at runtime by setting `$POSIXLY_CORRECT`):
  54
  55 ```
  56 #define GETOPT_PERMUTE_ARGS
  57 #define GETOPT_LONG_PERMUTE_ARGS
  58 #define GETOPT_LONG_ONLY_PERMUTE_ARGS
  59 ```
  60
  61 ---
  62
  63 ### strdup
  64
  65 includes `strdup()` and `strndup()`
  66
  67 `strndup()` follows the latest standard, meaning that it copies at most _n_ chars, not _n_ + 1.
  68 Also, no standard specifies that `strndup()` should return less than _n_ if `strlen(s) + 1` < _n_, but this implementation does so.
  69
  70 ---
  71
  72 ### strlcat
  73
  74 includes `strlcat()` and `strlcpy()`
  75
  76 ---
  77
  78 ### strtonum
  79
  80 includes `strtonum()`