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strlen(3)
NAME
  strlen - Finds the length of a string

LIBRARY
  Standard C Library (libc.so, libc.a)

SYNOPSIS
  #include <string.h>

  size_t strlen(
	  const char *s);

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  strlen():  ISO C, XPG4

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  s   Specifies the string.

DESCRIPTION
  The strlen() function returns the number of bytes in the string pointed to
  by the s parameter. The string length value does not include the
  terminating null character.



















				     Note
       If you pass a NULL pointer as the const char * parameter to the strlen
       function, the function generates a segmentation violation.  To avoid
       the segmentation violation and cause the function to return 0 (zero),
       change the NULL pointer treatment for the process before issuing the
       call to the strlen function, as follows:

	1.
	 Include the system header file sys/uswitch.h.

	2.
	 Call the uswitch function, as described in the uswitch(3) reference
	 page.

       The following program illustrates this procedure:

	    #include <stdio.h>
	    #include <sys/types.h>
	    #include <sys/uswitch.h>

	    main()
	    {
		    size_t  retval;
		    int	    uswitch_val;

		    uswitch_val = uswitch(USC_GET,0);
		    uswitch(USC_SET, uswitch_val | USW_NULLP);
		    retval = strlen(NULL);

RETURN VALUES
  On successful completion, the strlen() function returns the number of
  characters (bytes) in the string to which the s parameter points.  Current
  industry standards specify that no value be reserved to indicate an error.

RELATED INFORMATION
  Functions: string(3), uswitch(3), wcslen(3)

  Standards: standards(5)