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2964 need POSIX 2008 locale object support
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Gordon Ross <gordon.ross@nexenta.com>
Approved by: TBD
   1 '\" te

   2 .\" Copyright 1989 AT&T.  Copyright (c) 1992, X/Open Company Limited  All Rights Reserved.  Portions Copyright (c) 2005, Sun Microsystems, Inc.  All Rights Reserved.
   3 .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
   4 .\" http://www.opengroup.org/bookstore/.
   5 .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
   6 .\"  This notice shall appear on any product containing this material.
   7 .\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
   8 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
   9 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
  10 .TH CTYPE 3C "Jan 28, 2005"
  11 .SH NAME
  12 ctype, isalpha, isalnum, isascii, isblank, iscntrl, isdigit, islower, isprint,
  13 isspace, isupper, ispunct, isgraph, isxdigit \- character handling


  14 .SH SYNOPSIS
  15 .LP
  16 .nf
  17 #include <ctype.h>
  18 
  19 \fBint\fR \fBisalpha\fR(\fBint\fR \fIc\fR);
  20 .fi
  21 
  22 .LP
  23 .nf
  24 \fBint\fR \fBisalnum\fR(\fBint\fR \fIc\fR);
  25 .fi
  26 
  27 .LP
  28 .nf
  29 \fBint\fR \fBisascii\fR(\fBint\fR \fIc\fR);
  30 .fi
  31 
  32 .LP
  33 .nf
  34 \fBint\fR \fBisblank\fR(\fBint\fR \fIc\fR);
  35 .fi
  36 
  37 .LP
  38 .nf
  39 \fBint\fR \fBiscntrl\fR(\fBint\fR \fIc\fR);
  40 .fi
  41 
  42 .LP
  43 .nf
  44 \fBint\fR \fBisdigit\fR(\fBint\fR \fIc\fR);
  45 .fi
  46 
  47 .LP
  48 .nf
  49 \fBint\fR \fBisgraph\fR(\fBint\fR \fIc\fR);
  50 .fi
  51 
  52 .LP
  53 .nf
  54 \fBint\fR \fBislower\fR(\fBint\fR \fIc\fR);
  55 .fi
  56 
  57 .LP
  58 .nf
  59 \fBint\fR \fBisprint\fR(\fBint\fR \fIc\fR);
  60 .fi
  61 
  62 .LP
  63 .nf
  64 \fBint\fR \fBispunct\fR(\fBint\fR \fIc\fR);
  65 .fi
  66 
  67 .LP
  68 .nf
  69 \fBint\fR \fBisspace\fR(\fBint\fR \fIc\fR);
  70 .fi
  71 
  72 .LP
  73 .nf
  74 \fBint\fR \fBisupper\fR(\fBint\fR \fIc\fR);
  75 .fi
  76 
  77 .LP
  78 .nf
  79 \fBint\fR \fBisxdigit\fR(\fBint\fR \fIc\fR);
  80 .fi
  81 











































  82 .SH DESCRIPTION
  83 .sp
  84 .LP
  85 These macros classify character-coded integer values. Each is a predicate
  86 returning non-zero for true, \fB0\fR for false. The behavior of these macros,
  87 except \fBisascii()\fR, is affected by the current locale (see
  88 \fBsetlocale\fR(3C)). To modify the behavior, change the \fBLC_TYPE\fR category
  89 in  \fBsetlocale()\fR, that is, \fBsetlocale(\fR\fBLC_CTYPE\fR,
  90 \fInewlocale\fR). In the "C" locale, or in a locale where character type
  91 information is not defined, characters are classified according to the rules of
  92 the \fBUS-ASCII\fR 7-bit coded character set.
  93 .sp
  94 .LP








  95 The \fBisascii()\fR macro is defined on all integer values. The rest are
  96 defined only where the argument is an \fBint\fR, the value of which is
  97 representable as an \fBunsigned char\fR, or \fBEOF\fR, which is defined by the
  98 <\fBstdio.h\fR> header and represents end-of-file.
  99 .sp
 100 .LP
 101 Functions exist for all the macros defined below. To get the function form, the
 102 macro name must be undefined (for example, \fB#undef isdigit\fR).
 103 .sp
 104 .LP
 105 For macros described with \fBDefault\fR and \fBStandard conforming\fR versions,
 106 standard-conforming behavior is provided for standard-conforming applications
 107 (see \fBstandards\fR(5)) and for applications that define
 108 \fB__XPG4_CHAR_CLASS__\fR before including <\fBctype.h\fR>.
 109 .SS "Default"
 110 .sp
 111 .ne 2
 112 .na
 113 \fB\fBisalpha()\fR\fR
 114 .ad
 115 .RS 13n
 116 Tests for any character for which \fBisupper()\fR or \fBislower()\fR is true.
 117 .RE
 118 
 119 .SS "Standard conforming"
 120 .sp
 121 .ne 2
 122 .na
 123 \fB\fBisalpha()\fR\fR
 124 .ad
 125 .RS 13n
 126 Tests for any character for which \fBisupper()\fR or \fBislower()\fR is true,
 127 or any character that is one of the current locale-defined set of characters
 128 for which none of \fBiscntrl()\fR, \fBisdigit()\fR, \fBispunct()\fR, or
 129 \fBisspace()\fR is true. In "C" locale, \fBisalpha()\fR returns true only for
 130 the characters for which \fBisupper()\fR or \fBislower()\fR is true.
 131 .RE
 132 
 133 .sp
 134 .ne 2
 135 .na
 136 \fB\fBisalnum()\fR\fR
 137 .ad
 138 .RS 13n
 139 Tests for any character for which \fBisalpha()\fR or \fBisdigit()\fR is true
 140 (letter or digit).
 141 .RE
 142 
 143 .sp
 144 .ne 2
 145 .na


 161 .RE
 162 
 163 .sp
 164 .ne 2
 165 .na
 166 \fB\fBiscntrl()\fR\fR
 167 .ad
 168 .RS 13n
 169 Tests for any ``control character'' as defined by the character set.
 170 .RE
 171 
 172 .sp
 173 .ne 2
 174 .na
 175 \fB\fBisdigit()\fR\fR
 176 .ad
 177 .RS 13n
 178 Tests for any decimal-digit character.
 179 .RE
 180 
 181 .SS "Default"
 182 .sp
 183 .ne 2
 184 .na
 185 \fB\fBisgraph()\fR\fR
 186 .ad
 187 .RS 13n
 188 Tests for any character for which \fBispunct()\fR, \fBisupper()\fR,
 189 \fBislower()\fR, and \fBisdigit()\fR is true.
 190 .RE
 191 
 192 .SS "Standard conforming"
 193 .sp
 194 .ne 2
 195 .na
 196 \fB\fBisgraph()\fR\fR
 197 .ad
 198 .RS 13n
 199 Tests for any character for which \fBisalnum()\fR and \fBispunct()\fR are true,
 200 or any character in the current locale-defined "graph" class which is neither a
 201 space ("\|") nor a character for which \fBiscntrl()\fR is true.
 202 .RE
 203 
 204 .sp
 205 .ne 2
 206 .na
 207 \fB\fBislower()\fR\fR
 208 .ad
 209 .RS 13n
 210 Tests for any character that is a lower-case letter or is one of the current
 211 locale-defined set of characters for which none of \fBiscntrl()\fR,
 212 \fBisdigit()\fR, \fBispunct()\fR, \fBisspace()\fR, or \fBisupper()\fR is true.
 213 In the "C" locale, \fBislower()\fR returns true only for the characters defined
 214 as lower-case \fBASCII\fR characters.
 215 .RE
 216 
 217 .SS "Default"
 218 .sp
 219 .ne 2
 220 .na
 221 \fB\fBisprint()\fR\fR
 222 .ad
 223 .RS 13n
 224 Tests for any character for which \fBispunct()\fR, \fBisupper()\fR,
 225 \fBislower()\fR, \fBisdigit()\fR, and the space character ("\|") is true.
 226 .RE
 227 
 228 .SS "Standard conforming"
 229 .sp
 230 .ne 2
 231 .na
 232 \fB\fBisprint()\fR\fR
 233 .ad
 234 .RS 13n
 235 Tests for any character for which \fBiscntrl()\fR is false, and
 236 \fBisalnum()\fR, \fBisgraph()\fR, \fBispunct()\fR, the space character ("\|"),
 237 and the characters in the current locale-defined "print" class are true.
 238 .RE
 239 
 240 .sp
 241 .ne 2
 242 .na
 243 \fB\fBispunct()\fR\fR
 244 .ad
 245 .RS 13n
 246 Tests for any printing character which is neither a space ("\|") nor a
 247 character for which \fBisalnum()\fR or \fBiscntrl()\fR is true.
 248 .RE
 249 
 250 .sp
 251 .ne 2
 252 .na
 253 \fB\fBisspace()\fR\fR
 254 .ad
 255 .RS 13n
 256 Tests for any space, tab, carriage-return, newline, vertical-tab or form-feed
 257 (standard white-space characters) or for one of the current locale-defined set
 258 of characters for which \fBisalnum()\fR is false.  In the "C" locale,
 259 \fBisspace()\fR returns true only for the standard white-space characters.
 260 .RE
 261 
 262 .sp
 263 .ne 2
 264 .na
 265 \fB\fBisupper()\fR\fR
 266 .ad
 267 .RS 13n
 268 Tests for any character that is an upper-case letter or is one of the current
 269 locale-defined set of characters for which none of \fBiscntrl()\fR,
 270 \fBisdigit()\fR, \fBispunct()\fR, \fBisspace()\fR, or \fBislower()\fR is true.
 271 In the "C" locale, \fBisupper()\fR returns true only for the characters defined
 272 as upper-case \fBASCII\fR characters.
 273 .RE
 274 
 275 .SS "Default"
 276 .sp
 277 .ne 2
 278 .na
 279 \fB\fBisxdigit()\fR\fR
 280 .ad
 281 .RS 14n
 282 Tests for any hexadecimal-digit character (\fB[0\(mi9]\fR, \fB[A\(miF]\fR, or
 283 \fB[a\(mif]\fR).
 284 .RE
 285 
 286 .SS "Standard conforming"
 287 .sp
 288 .ne 2
 289 .na
 290 \fB\fBisxdigit()\fR\fR
 291 .ad
 292 .RS 14n
 293 Tests for any hexadecimal-digit character (\fB[0\(mi9]\fR, \fB[A\(miF]\fR, or
 294 \fB[a\(mif]\fR or the current locale-defined sets of characters representing
 295 the hexadecimal digits \fB10\fR to \fB15\fR inclusive). In the "C" locale, only
 296 .sp
 297 .in +2
 298 .nf
 299 0 1 2 3 4 5 6 7 8 9 A B C D E F a b c d e f
 300 .fi
 301 .in -2
 302 
 303 are included.
 304 .RE
 305 
 306 .SH RETURN VALUES
 307 .sp
 308 .LP
 309 If the argument to any of the character handling macros is not in the domain of
 310 the function, the result is undefined. Otherwise, the macro or function returns
 311 non-zero if the classification is \fBTRUE\fR and \fB0\fR if the classification
 312 is \fBFALSE\fR.
 313 .SH USAGE
 314 .sp
 315 .LP
 316 These macros or functions can be used safely in multithreaded applications, as
 317 long as \fBsetlocale\fR(3C) is not being called to change the locale.
 318 .SH ATTRIBUTES
 319 .sp
 320 .LP
 321 See \fBattributes\fR(5) for descriptions of the following attributes:
 322 .sp
 323 
 324 .sp
 325 .TS
 326 box;
 327 l l
 328 l l .
 329 ATTRIBUTE TYPE  ATTRIBUTE VALUE

 330 CSI     Enabled

 331 Interface Stability     Standard
 332 MT-Level        MT-Safe with exceptions

 333 .TE
 334 
 335 .SH SEE ALSO
 336 .sp
 337 .LP
 338 \fBsetlocale\fR(3C), \fBstdio\fR(3C), \fBascii\fR(5), \fBenviron\fR(5),

 339 \fBstandards\fR(5)
   1 '\" te
   2 .\" Copyright 2014 Garrett D'Amore <garrett@damore.org>
   3 .\" Copyright 1989 AT&T.  Copyright (c) 1992, X/Open Company Limited  All Rights Reserved.  Portions Copyright (c) 2005, Sun Microsystems, Inc.  All Rights Reserved.
   4 .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
   5 .\" http://www.opengroup.org/bookstore/.
   6 .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
   7 .\"  This notice shall appear on any product containing this material.
   8 .\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
   9 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
  10 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
  11 .TH CTYPE 3C "Jun 27, 2014"
  12 .SH NAME
  13 ctype, isalpha, isalnum, isascii, isblank, iscntrl, isdigit, islower,
  14 isprint, isspace, isupper, ispunct, isgraph, isxdigit, isalpha_l,
  15 isalnum_l, isblank_l, iscntrl_l, isdigit_l, islower_l, isprint_l,
  16 isspace_l, isupper_l, ispunct_l, isgraph_l \- character handling
  17 .SH SYNOPSIS
  18 .LP
  19 .nf
  20 #include <ctype.h>
  21 
  22 \fBint\fR \fBisalpha\fR(\fBint\fR \fIc\fR);
  23 .fi

  24 .LP
  25 .nf
  26 \fBint\fR \fBisalnum\fR(\fBint\fR \fIc\fR);
  27 .fi

  28 .LP
  29 .nf
  30 \fBint\fR \fBisascii\fR(\fBint\fR \fIc\fR);
  31 .fi

  32 .LP
  33 .nf
  34 \fBint\fR \fBisblank\fR(\fBint\fR \fIc\fR);
  35 .fi

  36 .LP
  37 .nf
  38 \fBint\fR \fBiscntrl\fR(\fBint\fR \fIc\fR);
  39 .fi

  40 .LP
  41 .nf
  42 \fBint\fR \fBisdigit\fR(\fBint\fR \fIc\fR);
  43 .fi

  44 .LP
  45 .nf
  46 \fBint\fR \fBisgraph\fR(\fBint\fR \fIc\fR);
  47 .fi

  48 .LP
  49 .nf
  50 \fBint\fR \fBislower\fR(\fBint\fR \fIc\fR);
  51 .fi

  52 .LP
  53 .nf
  54 \fBint\fR \fBisprint\fR(\fBint\fR \fIc\fR);
  55 .fi

  56 .LP
  57 .nf
  58 \fBint\fR \fBispunct\fR(\fBint\fR \fIc\fR);
  59 .fi

  60 .LP
  61 .nf
  62 \fBint\fR \fBisspace\fR(\fBint\fR \fIc\fR);
  63 .fi

  64 .LP
  65 .nf
  66 \fBint\fR \fBisupper\fR(\fBint\fR \fIc\fR);
  67 .fi

  68 .LP
  69 .nf
  70 \fBint\fR \fBisxdigit\fR(\fBint\fR \fIc\fR);
  71 .fi
  72 .LP
  73 .nf
  74 \fBint\fR \fBisalpha_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  75 .fi
  76 .LP
  77 .nf
  78 \fBint\fR \fBisalnum_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  79 .fi
  80 .LP
  81 .nf
  82 \fBint\fR \fBisblank_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  83 .fi
  84 .LP
  85 .nf
  86 \fBint\fR \fBiscntrl_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  87 .fi
  88 .LP
  89 .nf
  90 \fBint\fR \fBisdigit_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  91 .fi
  92 .LP
  93 .nf
  94 \fBint\fR \fBisgraph_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  95 .fi
  96 .LP
  97 .nf
  98 \fBint\fR \fBislower_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
  99 .fi
 100 .LP
 101 .nf
 102 \fBint\fR \fBisprint_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
 103 .fi
 104 .LP
 105 .nf
 106 \fBint\fR \fBispunct_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
 107 .fi
 108 .LP
 109 .nf
 110 \fBint\fR \fBisspace_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
 111 .fi
 112 .LP
 113 .nf
 114 \fBint\fR \fBisupper_l\fR(\fBint\fR \fIc\fR, \fBlocale_t\fR \fIloc\fR);
 115 .fi
 116 .SH DESCRIPTION

 117 .LP
 118 These functions classify character-coded integer values. Each is a
 119 predicate returning non-zero for true, \fB0\fR for false. The behavior
 120 of these macros, except \fBisascii()\fR, is affected by the current
 121 locale (see \fBsetlocale\fR(3C) and \fBuselocale\fR(3C)). To modify
 122 the behavior, change the \fBLC_TYPE\fR category in \fBsetlocale()\fR, that is,
 123 \fBsetlocale(\fR\fBLC_CTYPE\fR, \fInewlocale\fR). In the "C" locale,
 124 or in a locale where character type information is not defined,
 125 characters are classified according to the rules of the \fBUS-ASCII\fR
 126 7-bit coded character set.
 127 .LP
 128 The functions \fBisalnum_l()\fR, \fBisalpha_l()\fR, \fBisblank_l()\fR,
 129 \fBiscntrl_l\fR, \fBisdigit_l()\fR, \fBislower_l()\fR,
 130 \fBisprint_l()\fR, \fBispunct_l()\fR, \fBisspace_l()\fR,
 131 \fBisupper_l()\fR, all behave identically to their counterparts without
 132 the '\fB_l\fR' prefix, except that instead of acting on the current
 133 locale, that perform the test on the locale specified in the argument
 134 \fIloc\fR.
 135 .LP
 136 The \fBisascii()\fR macro is defined on all integer values. The rest are
 137 defined only where the argument is an \fBint\fR, the value of which is
 138 representable as an \fBunsigned char\fR, or \fBEOF\fR, which is defined by the
 139 <\fBstdio.h\fR> header and represents end-of-file.
 140 .sp











 141 .ne 2
 142 .na
 143 \fB\fBisalpha()\fR\fR
 144 .ad
 145 .RS 13n










 146 Tests for any character for which \fBisupper()\fR or \fBislower()\fR is true,
 147 or any character that is one of the current locale-defined set of characters
 148 for which none of \fBiscntrl()\fR, \fBisdigit()\fR, \fBispunct()\fR, or
 149 \fBisspace()\fR is true. In "C" locale, \fBisalpha()\fR returns true only for
 150 the characters for which \fBisupper()\fR or \fBislower()\fR is true.
 151 .RE
 152 
 153 .sp
 154 .ne 2
 155 .na
 156 \fB\fBisalnum()\fR\fR
 157 .ad
 158 .RS 13n
 159 Tests for any character for which \fBisalpha()\fR or \fBisdigit()\fR is true
 160 (letter or digit).
 161 .RE
 162 
 163 .sp
 164 .ne 2
 165 .na


 181 .RE
 182 
 183 .sp
 184 .ne 2
 185 .na
 186 \fB\fBiscntrl()\fR\fR
 187 .ad
 188 .RS 13n
 189 Tests for any ``control character'' as defined by the character set.
 190 .RE
 191 
 192 .sp
 193 .ne 2
 194 .na
 195 \fB\fBisdigit()\fR\fR
 196 .ad
 197 .RS 13n
 198 Tests for any decimal-digit character.
 199 .RE
 200 

 201 .sp
 202 .ne 2
 203 .na
 204 \fB\fBisgraph()\fR\fR
 205 .ad
 206 .RS 13n











 207 Tests for any character for which \fBisalnum()\fR and \fBispunct()\fR are true,
 208 or any character in the current locale-defined "graph" class which is neither a
 209 space ("\|") nor a character for which \fBiscntrl()\fR is true.
 210 .RE
 211 
 212 .sp
 213 .ne 2
 214 .na
 215 \fB\fBislower()\fR\fR
 216 .ad
 217 .RS 13n
 218 Tests for any character that is a lower-case letter or is one of the current
 219 locale-defined set of characters for which none of \fBiscntrl()\fR,
 220 \fBisdigit()\fR, \fBispunct()\fR, \fBisspace()\fR, or \fBisupper()\fR is true.
 221 In the "C" locale, \fBislower()\fR returns true only for the characters defined
 222 as lower-case \fBASCII\fR characters.
 223 .RE
 224 

 225 .sp
 226 .ne 2
 227 .na
 228 \fB\fBisprint()\fR\fR
 229 .ad
 230 .RS 13n











 231 Tests for any character for which \fBiscntrl()\fR is false, and
 232 \fBisalnum()\fR, \fBisgraph()\fR, \fBispunct()\fR, the space character ("\|"),
 233 and the characters in the current locale-defined "print" class are true.
 234 .RE
 235 
 236 .sp
 237 .ne 2
 238 .na
 239 \fB\fBispunct()\fR\fR
 240 .ad
 241 .RS 13n
 242 Tests for any printing character which is neither a space ("\|") nor a
 243 character for which \fBisalnum()\fR or \fBiscntrl()\fR is true.
 244 .RE
 245 
 246 .sp
 247 .ne 2
 248 .na
 249 \fB\fBisspace()\fR\fR
 250 .ad
 251 .RS 13n
 252 Tests for any space, tab, carriage-return, newline, vertical-tab or form-feed
 253 (standard white-space characters) or for one of the current locale-defined set
 254 of characters for which \fBisalnum()\fR is false.  In the "C" locale,
 255 \fBisspace()\fR returns true only for the standard white-space characters.
 256 .RE
 257 
 258 .sp
 259 .ne 2
 260 .na
 261 \fB\fBisupper()\fR\fR
 262 .ad
 263 .RS 13n
 264 Tests for any character that is an upper-case letter or is one of the current
 265 locale-defined set of characters for which none of \fBiscntrl()\fR,
 266 \fBisdigit()\fR, \fBispunct()\fR, \fBisspace()\fR, or \fBislower()\fR is true.
 267 In the "C" locale, \fBisupper()\fR returns true only for the characters defined
 268 as upper-case \fBASCII\fR characters.
 269 .RE
 270 

 271 .sp
 272 .ne 2
 273 .na
 274 \fB\fBisxdigit()\fR\fR
 275 .ad
 276 .RS 14n
 277 Tests for any hexadecimal-digit character (\fB[0\(mi9]\fR, \fB[A\(miF]\fR, or











 278 \fB[a\(mif]\fR or the current locale-defined sets of characters representing
 279 the hexadecimal digits \fB10\fR to \fB15\fR inclusive). In the "C" locale, only
 280 .sp
 281 .in +2
 282 .nf
 283 0 1 2 3 4 5 6 7 8 9 A B C D E F a b c d e f
 284 .fi
 285 .in -2
 286 
 287 are included.
 288 .RE
 289 
 290 .SH RETURN VALUES

 291 .LP
 292 If the argument to any of the character handling macros is not in the domain of
 293 the function, the result is undefined. Otherwise, the macro or function returns
 294 non-zero if the classification is \fBTRUE\fR and \fB0\fR if the classification
 295 is \fBFALSE\fR.





 296 .SH ATTRIBUTES
 297 .sp
 298 .LP
 299 See \fBattributes\fR(5) for descriptions of the following attributes:



 300 .TS
 301 box;
 302 c | c
 303 l | l .
 304 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 305 _
 306 CSI     Enabled
 307 _
 308 Interface Stability     Standard
 309 _
 310 MT-Level        MT-Safe
 311 .TE
 312 
 313 .SH SEE ALSO

 314 .LP
 315 \fBnewlocale\fR(3C), \fBsetlocale\fR(3C), \fBuselocale\fR(3C),
 316 \fBstdio\fR(3C), \fBascii\fR(5), \fBenviron\fR(5),
 317 \fBstandards\fR(5)