strlen (original) (raw)

The Open Group Base Specifications Issue 6
IEEE Std 1003.1, 2004 Edition
Copyright © 2001-2004 The IEEE and The Open Group, All Rights reserved.

A newer edition of this document exists here

NAME

strlen - get string length

SYNOPSIS

`#include <string.h>

size_t strlen(const char *

s);
`

DESCRIPTION

[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of IEEE Std 1003.1-2001 defers to the ISO C standard.

The strlen() function shall compute the number of bytes in the string to which s points, not including the terminating null byte.

RETURN VALUE

The strlen() function shall return the length of s; no return value shall be reserved to indicate an error.

ERRORS

No errors are defined.

The following sections are informative.

EXAMPLES

Getting String Lengths

The following example sets the maximum length of key and data by using strlen() to get the lengths of those strings.

#include <string.h> ... struct element { char *key; char *data; }; ... char *key, *data; int len;

*keylength = *datalength = 0; ... if ((len = strlen(key)) > *keylength) *keylength = len; if ((len = strlen(data)) > *datalength) *datalength = len; ...

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

The Base Definitions volume of IEEE Std 1003.1-2001, <string.h>

CHANGE HISTORY

First released in Issue 1. Derived from Issue 1 of the SVID.

Issue 5

The RETURN VALUE section is updated to indicate that strlen() returns the length of s, and not s itself as was previously stated.

End of informative text.

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