ispunct(3)

ispunct3

Punctuation character test

Usage

#include <ctype.h>

int

ispunct(int c);

int

ispunct_l(int c, locale_t loc);

Library

Standard C Library (libc, -lc)

Overview

The ispunct() and ispunct_l() functions test for any printing character except for space (‘ ’) or a character for which isalnum(3) or isalnum_l(3) is true. The value of the argument must be representable as an unsigned char or the value of EOF.

In the ASCII character set, this includes the following characters (with their numeric values shown in octal):

041 ``!''042 ``"''043 ``#''044 ``$''045 ``%''
046 ``&''047 ``'''050 ``(''051 ``)''052 ``*''
053 ``+''054 ``,''055 ``-''056 ``.''057 ``/''
072 ``:''073 ``;''074 ``<''075 ``=''076 ``>''
077 ``?''100 ``@''133 ``[''134 ``\''135 ``]''
136 ``^''137 ``_''140 ```''173 ``{''174 ``|''
175 ``}''176 ``~''

The ispunct_l() function takes an explicit locale argument, whereas the ispunct() function uses the current global or per-thread locale.

Return values

The ispunct() and ispunct_l() functions return zero if the character tests false and return non-zero if the character tests true.

Compatibility

The 4.4BSD extension of accepting arguments outside of the range of the unsigned char type in locales with large character sets is considered obsolete and may not be supported in future releases. The iswpunct() or iswpunct_l() function should be used instead.

Releases

87 releases since FreeBSD 2.0.5-RELEASE; the text changed 45 times.

  1. 2.0.5–2.1.7.1
  2. 2.2.2
  3. 2.2.5–3.4
  4. 3.5–3.5.1
  5. 4.0
  6. 4.1
  7. 4.1.1–4.2
  8. 4.3–4.4
  9. 4.5–4.11
  10. 5.0–5.2.1
  11. 5.3–5.5
  12. 6.0–6.3
  13. 6.4
  14. 7.0
  15. 7.1
  16. 7.2
  17. 7.3
  18. 7.4
  19. 8.0
  20. 8.1
  21. 8.2
  22. 8.3
  23. 8.4
  24. 9.0
  25. 9.1
  26. 9.2
  27. 9.3
  28. 10.0
  29. 10.1
  30. 10.2
  31. 10.3
  32. 10.4
  33. 11.0
  34. 11.1
  35. 11.2
  36. 11.3
  37. 11.4
  38. 12.0
  39. 12.1
  40. 12.2
  41. 12.3
  42. 12.4
  43. 13.0–13.1
  44. 13.2
  45. 13.3–14.5
  46. 15.0–16.0

Standards

The ispunct() function conforms to ISO/IEC 9899:1990 (“ISO C90”). The ispunct_l() function conforms to IEEE Std 1003.1-2008 (“POSIX.1”).

History

The ispunct() function first appeared in Version 7 AT&T UNIX.

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.