man3/strspn.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
   2 .\"
   3 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   4 .\"
   5 .\" References consulted:
   6 .\"     Linux libc source code
   7 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
   8 .\"     386BSD man pages
   9 .\" Modified Sat Jul 24 17:57:50 1993 by Rik Faith (faith@cs.unc.edu)
  10 .TH STRSPN 3 2021-03-22 "Linux man-pages (unreleased)"
  11 .SH NAME
  12 strspn, strcspn \- get length of a prefix substring
  13 .SH LIBRARY
  14 Standard C library
  15 .RI ( libc ", " \-lc )
  16 .SH SYNOPSIS
  17 .nf
  18 .B #include <string.h>
  19 .PP
  20 .BI "size_t strspn(const char *" s ", const char *" accept );
  21 .BI "size_t strcspn(const char *" s ", const char *" reject );
  22 .fi
  23 .SH DESCRIPTION
  24 The
  25 .BR strspn ()
  26 function calculates the length (in bytes) of the initial
  27 segment of
  28 .I s
  29 which consists entirely of bytes in
  30 .IR accept .
  31 .PP
  32 The
  33 .BR strcspn ()
  34 function calculates the length of the initial
  35 segment of
  36 .I s
  37 which consists entirely of bytes not in
  38 .IR reject .
  39 .SH RETURN VALUE
  40 The
  41 .BR strspn ()
  42 function returns the number of bytes in
  43 the initial segment of
  44 .I s
  45 which consist only of bytes
  46 from
  47 .IR accept .
  48 .PP
  49 The
  50 .BR strcspn ()
  51 function returns the number of bytes in
  52 the initial segment of
  53 .I s
  54 which are not in the string
  55 .IR reject .
  56 .SH ATTRIBUTES
  57 For an explanation of the terms used in this section, see
  58 .BR attributes (7).
  59 .ad l
  60 .nh
  61 .TS
  62 allbox;
  63 lbx lb lb
  64 l l l.
  65 Interface       Attribute       Value
  66 T{
  67 .BR strspn (),
  68 .BR strcspn ()
  69 T}      Thread safety   MT-Safe
  70 .TE
  71 .hy
  72 .ad
  73 .sp 1
  74 .SH STANDARDS
  75 POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.
  76 .SH SEE ALSO
  77 .BR index (3),
  78 .BR memchr (3),
  79 .BR rindex (3),
  80 .BR strchr (3),
  81 .BR string (3),
  82 .BR strpbrk (3),
  83 .BR strsep (3),
  84 .BR strstr (3),
  85 .BR strtok (3),
  86 .BR wcscspn (3),
  87 .BR wcsspn (3)