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isgraph |
Portability: | ISO/ANSI C conforming, UNIX compatible |
SYNOPSIS | |
DESCRIPTION | |
RETURN VALUE | |
CAUTION | |
IMPLEMENTATION | |
EXAMPLE | |
RELATED FUNCTIONS | |
SEE ALSO |
SYNOPSIS |
#include <ctype.h> int isgraph(int c);
DESCRIPTION |
isgraph
tests an integer value
c
to determine whether
it is a graphic character. (See IMPLEMENTATION below for a discussion of
how a graphic character is defined in the 370 environment.)
RETURN VALUE |
isgraph
returns 0 if the character is not a graphic character, or a nonzero value
if it is. If the argument is
EOF
, 0 is
returned.
CAUTION |
The effect of
isgraph
on a noncharacter argument other than
EOF
is undefined. Do not assume that
isgraph
returns either 0 or
1.
Note:
For some EBCDIC
characters, neither
iscntrl(c)
,
isspace(c)
, nor
isgraph(c)
is true,
even though this identity is sometimes used as a definition of
isgraph
. If
isprint(c)
is true,
either
isspace(c)
or
isgraph(c)
is also true.
IMPLEMENTATION |
Not all characters considered printable in ASCII are considered printable in EBCDIC.
In the 5370 locale,
isgraph
returns a non-zero value for nonblank characters that are present
on the 1403 PN print train. These characters include the digits and letters,
plus these special characters:
| @ # $ % ¬ * ( ) - _ = + : ; " ' , . / ? < > &
This is the set of characters whose printability is guaranteed, regardless of device type. Note that a number of characters used by the C language, including the backslash, the exclamation point, the brackets, and the braces, are not included as graphic characters according to this definition.
In the POSIX locale,
isgraph
returns the results that are expected in an ASCII environment.
EXAMPLE |
#include <ctype.h> #include <stdio.h> #include <string.h> main() { char *str; char input[20]; size_t len; int gcount = 0; puts("Enter a string:"); str = gets(input); len = strlen(str); /* Test whether all characters in a string are graphic. */ while (isgraph(*str)) { ++gcount; ++str; } if (len == gcount) puts("The string entered is entirely graphic."); else puts("String is not entirely graphic."); }
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SEE ALSO |
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