newlib/libc/ctype/isprint.c

   1 /*
   2 FUNCTION
   3         <<isprint>>, <<isgraph>>, <<isprint_l>>, <<isgraph_l>>---printable character predicates
   4
   5 INDEX
   6         isprint
   7
   8 INDEX
   9         isgraph
  10
  11 INDEX
  12         isprint_l
  13
  14 INDEX
  15         isgraph_l
  16
  17 SYNOPSIS
  18         #include <ctype.h>
  19         int isprint(int <[c]>);
  20         int isgraph(int <[c]>);
  21
  22         #include <ctype.h>
  23         int isprint_l(int <[c]>, locale_t <[locale]>);
  24         int isgraph_l(int <[c]>, locale_t <[locale]>);
  25
  26 DESCRIPTION
  27 <<isprint>> is a macro which classifies singlebyte charset values by table
  28 lookup.  It is a predicate returning non-zero for printable characters,
  29 and 0 for other character arguments.  It is defined only if <[c]> is
  30 representable as an unsigned char or if <[c]> is EOF.
  31
  32 <<isgraph>> behaves identically to <<isprint>>, except that space characters
  33 are excluded.
  34
  35 <<isprint_l>>, <<isgraph_l>> are like <<isprint>>, <<isgraph>> but perform
  36 the check based on the locale specified by the locale object locale.  If
  37 <[locale]> is LC_GLOBAL_LOCALE or not a valid locale object, the behaviour
  38 is undefined.
  39
  40 You can use a compiled subroutine instead of the macro definition by
  41 undefining either macro using `<<#undef isprint>>' or `<<#undef isgraph>>',
  42 or `<<#undef isprint_l>>' or `<<#undef isgraph_l>>'.
  43
  44 RETURNS
  45 <<isprint>>, <<isprint_l>> return non-zero if <[c]> is a printing character.
  46 <<isgraph>>, <<isgraph_l>> return non-zero if <[c]> is a printing character
  47 except spaces.
  48
  49 PORTABILITY
  50 <<isprint>> and <<isgraph>> are ANSI C.
  51
  52 No supporting OS subroutines are required.
  53 */
  54
  55 #include <_ansi.h>
  56 #include <ctype.h>
  57
  58 #undef isgraph
  59 int
  60 isgraph (int c)
  61 {
  62         return(__CTYPE_PTR[c+1] & (_P|_U|_L|_N));
  63 }
  64
  65
  66 #undef isprint
  67 int
  68 isprint (int c)
  69 {
  70         return(__CTYPE_PTR[c+1] & (_P|_U|_L|_N|_B));
  71 }