man3/strnlen.3

   1 .\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
   2 .\"
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   8 .\" References consulted:
   9 .\"   GNU glibc-2 source code and manual
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  11 .TH STRNLEN 3  1999-07-25 "GNU" "Linux Programmer's Manual"
  12 .SH NAME
  13 strnlen \- determine the length of a fixed-size string
  14 .SH SYNOPSIS
  15 .nf
  16 .B #define _GNU_SOURCE
  17 .sp
  18 .B #include <string.h>
  19 .sp
  20 .BI "size_t strnlen(const char *" s ", size_t " maxlen );
  21 .fi
  22 .SH DESCRIPTION
  23 The \fBstrnlen\fP() function returns the number of characters in the string
  24 pointed to by \fIs\fP, not including the terminating '\\0' character, but
  25 at most \fImaxlen\fP. In doing this, \fBstrnlen\fP() looks only at the first
  26 \fImaxlen\fP characters at \fIs\fP and never beyond \fIs+maxlen\fP.
  27 .SH "RETURN VALUE"
  28 The \fBstrnlen\fP() function returns \fIstrlen(s)\fP, if that is less than
  29 \fImaxlen\fP, or \fImaxlen\fP if there is no '\\0' character among the first
  30 \fImaxlen\fP characters pointed to by \fIs\fP.
  31 .SH "CONFORMING TO"
  32 This function is a GNU extension.
  33 .SH "SEE ALSO"
  34 .BR strlen (3)