isblank - cppreference.com (original) (raw)
| | | | | ---------------------- | | ----------- | | int isblank( int ch ); | | (since C99) |
Checks if the given character is a blank character in the current C locale. In the default C locale, only space (0x20
) and horizontal tab (0x09
) are classified as blank.
The behavior is undefined if the value of ch is not representable as unsigned char and is not equal to EOF.
[edit] Parameters
ch | - | character to classify |
---|
[edit] Return value
Non-zero value if the character is a blank character, zero otherwise.
[edit] Example
#include <ctype.h> #include <limits.h> #include <stdio.h> int main(void) { for (int ndx = 0; ndx != UCHAR_MAX; ++ndx) if (isblank(ndx)) printf("0x%02x\n", ndx); }
Output:
[edit] References
C23 standard (ISO/IEC 9899:2024):
7.4.1.3 The isblank function (p: TBD)
C17 standard (ISO/IEC 9899:2018):
7.4.1.3 The isblank function (p: 145)
C11 standard (ISO/IEC 9899:2011):
7.4.1.3 The isblank function (p: 201)
C99 standard (ISO/IEC 9899:1999):
7.4.1.3 The isblank function (p: 182)
[edit] See also
ASCII values | characters | iscntrl iswcntrl | isprint iswprint | isspace iswspace | isblank iswblank | isgraph iswgraph | ispunct iswpunct | isalnum iswalnum | isalpha iswalpha | isupper iswupper | islower iswlower | isdigit iswdigit | isxdigit iswxdigit | ||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
decimal | hexadecimal | octal | |||||||||||||
0–8 | \x0–\x8 | \0–\10 | control codes (NUL, etc.) | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
9 | \x9 | \11 | tab (\t) | ≠0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
10–13 | \xA–\xD | \12–\15 | whitespaces (\n, \v, \f, \r) | ≠0 | 0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
14–31 | \xE–\x1F | \16–\37 | control codes | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
32 | \x20 | \40 | space | 0 | ≠0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
33–47 | \x21–\x2F | \41–\57 | !"#$%&'()*+,-./ | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
48–57 | \x30–\x39 | \60–\71 | 0123456789 | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | 0 | 0 | 0 | ≠0 | ≠0 |
58–64 | \x3A–\x40 | \72–\100 | :;<=>?@ | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
65–70 | \x41–\x46 | \101–\106 | ABCDEF | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | ≠0 | 0 | 0 | ≠0 |
71–90 | \x47–\x5A | \107–\132 | GHIJKLMNOPQRSTUVWXYZ | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | ≠0 | 0 | 0 | 0 |
91–96 | \x5B–\x60 | \133–\140 | [\]^_` | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
97–102 | \x61–\x66 | \141–\146 | abcdef | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | 0 | ≠0 | 0 | ≠0 |
103–122 | \x67–\x7A | \147–\172 | ghijklmnopqrstuvwxyz | 0 | ≠0 | 0 | 0 | ≠0 | 0 | ≠0 | ≠0 | 0 | ≠0 | 0 | 0 |
123–126 | \x7B–\x7E | \173–\176 | {|}~ | 0 | ≠0 | 0 | 0 | ≠0 | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 |
127 | \x7F | \177 | backspace character (DEL) | ≠0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |