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-rw-r--r--newlib/libc/ctype/iscntrl.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/newlib/libc/ctype/iscntrl.c b/newlib/libc/ctype/iscntrl.c
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+++ b/newlib/libc/ctype/iscntrl.c
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+
+/*
+FUNCTION
+ <<iscntrl>>---control character predicate
+
+INDEX
+ iscntrl
+
+ANSI_SYNOPSIS
+ #include <ctype.h>
+ int iscntrl(int <[c]>);
+
+TRAD_SYNOPSIS
+ #include <ctype.h>
+ int iscntrl(<[c]>);
+
+DESCRIPTION
+<<iscntrl>> is a macro which classifies ASCII integer values by table
+lookup. It is a predicate returning non-zero for control characters, and 0
+for other characters. It is defined only when <<isascii>>(<[c]>) is
+true or <[c]> is EOF.
+
+You can use a compiled subroutine instead of the macro definition by
+undefining the macro using `<<#undef iscntrl>>'.
+
+RETURNS
+<<iscntrl>> returns non-zero if <[c]> is a delete character or ordinary
+control character (<<0x7F>> or <<0x00>>--<<0x1F>>).
+
+PORTABILITY
+<<iscntrl>> is ANSI C.
+
+No supporting OS subroutines are required.
+*/
+
+#include <_ansi.h>
+#include <ctype.h>
+
+
+
+#undef iscntrl
+int
+_DEFUN(iscntrl,(c),int c)
+{
+ return((_ctype_ + 1)[c] & _C);
+}
+
+