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diff --git a/man3/isalpha.3 b/man3/isalpha.3 new file mode 100644 index 000000000..fc0622309 --- /dev/null +++ b/man3/isalpha.3 @@ -0,0 +1,160 @@ +.\" (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de) +.\" +.\" Permission is granted to make and distribute verbatim copies of this +.\" manual provided the copyright notice and this permission notice are +.\" preserved on all copies. +.\" +.\" Permission is granted to copy and distribute modified versions of this +.\" manual under the conditions for verbatim copying, provided that the +.\" entire resulting derived work is distributed under the terms of a +.\" permission notice identical to this one. +.\" +.\" Since the Linux kernel and libraries are constantly changing, this +.\" manual page may be incorrect or out-of-date. The author(s) assume no +.\" responsibility for errors or omissions, or for damages resulting from +.\" the use of the information contained herein. The author(s) may not +.\" have taken the same level of care in the production of this manual, +.\" which is licensed free of charge, as they might when working +.\" professionally. +.\" +.\" Formatted or processed versions of this manual, if unaccompanied by +.\" the source, must acknowledge the copyright and authors of this work. +.\" License. +.\" +.\" Modified Sat Jul 24 19:10:00 1993 by Rik Faith (faith@cs.unc.edu) +.\" Modified Sun Aug 21 17:51:50 1994 by Rik Faith (faith@cs.unc.edu) +.\" Modified Sat Sep 2 21:52:01 1995 by Jim Van Zandt <jrv@vanzandt.mv.com> +.\" Modified Mon May 27 22:55:26 1996 by Martin Schulze (joey@linux.de) +.\" +.TH ISALPHA 3 1995-09-02 "GNU" "Linux Programmer's Manual" +.SH NAME +isalnum, isalpha, isascii, isblank, iscntrl, isdigit, isgraph, islower, +isprint, ispunct, isspace, isupper, isxdigit \- character +classification routines +.SH SYNOPSIS +.nf +.B #include <ctype.h> +.sp +.BI "int isalnum(int " "c" ); +.nl +.BI "int isalpha(int " "c" ); +.nl +.BI "int isascii(int " "c" ); +.nl +.BI "int isblank(int " "c" ); +.nl +.BI "int iscntrl(int " "c" ); +.nl +.BI "int isdigit(int " "c" ); +.nl +.BI "int isgraph(int " "c" ); +.nl +.BI "int islower(int " "c" ); +.nl +.BI "int isprint(int " "c" ); +.nl +.BI "int ispunct(int " "c" ); +.nl +.BI "int isspace(int " "c" ); +.nl +.BI "int isupper(int " "c" ); +.nl +.BI "int isxdigit(int " "c" ); +.fi +.SH DESCRIPTION +These functions check whether +.IR c , +which must have the value of an +.B unsigned char +or +.BR EOF , +falls into a certain character class according to the current locale. +.TP +.B "isalnum()" +checks for an alphanumeric character; it is equivalent to +.BI "(isalpha(" c ") || isdigit(" c "))" \fR. +.TP +.B "isalpha()" +checks for an alphabetic character; in the standard \fB"C"\fP +locale, it is equivalent to +.BI "(isupper(" c ") || islower(" c "))" \fR. +In some locales, there may be additional characters for which +.B isalpha() +is true--letters which are neither upper case nor lower +case. +.TP +.B "isascii()" +checks whether \fIc\fP is a 7-bit +.I unsigned char +value that fits into +the ASCII character set. This function is a BSD extension +and is also an SVID extension. +.TP +.B "isblank()" +checks for a blank character; that is, a space or a tab. +.TP +.B "iscntrl()" +checks for a control character. +.TP +.B "isdigit()" +checks for a digit (0 through 9). +.TP +.B "isgraph()" +checks for any printable character except space. +.TP +.B "islower()" +checks for a lower-case character. +.TP +.B "isprint()" +checks for any printable character including space. +.TP +.B "ispunct()" +checks for any printable character which is not a space or an +alphanumeric character. +.TP +.B "isspace()" +checks for white-space characters. In the +.B """C""" +and +.B """POSIX""" +locales, these are: space, form-feed +.RB ( '\ef' ), +newline +.RB ( '\en' ), +carriage return +.RB ( '\er' ), +horizontal tab +.RB ( '\et' ), +and vertical tab +.RB ( '\ev' ). +.TP +.B "isupper()" +checks for an uppercase letter. +.TP +.B "isxdigit()" +checks for a hexadecimal digits, i.e. one of +.nl +.BR "0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F" . +.SH "RETURN VALUE" +The values returned are nonzero if the character +.I c +falls into the tested class, and a zero value +if not. +.SH "CONFORMING TO" +ANSI - C, BSD 4.3. +\fBisascii()\fP is a BSD extension +and is also an SVID extension. +\fBisblank()\fP conforms to ISO C99 7.4.1.3. +.SH NOTE +The details of what characters belong into which class depend on the current +locale. For example, +.B isupper() +will not recognize an A - umlaut as an uppercase letter in the default +.B "C" +locale. +.SH "SEE ALSO" +.BR setlocale (3), +.BR tolower (3), +.BR toupper (3), +.BR ascii (7), +.BR locale (7) |