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FGETS(3)	       FreeBSD Library Functions Manual		      FGETS(3)

NAME
     fgets, gets -- get	a line from a stream

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <stdio.h>

     char *
     fgets(char	* restrict str,	int size, FILE * restrict stream);

     char *
     gets(char *str);

DESCRIPTION
     The fgets() function reads	at most	one less than the number of characters
     specified by size from the	given stream and stores	them in	the string
     str.  Reading stops when a	newline	character is found, at end-of-file or
     error.  The newline, if any, is retained.	If any characters are read and
     there is no error,	a `\0' character is appended to	end the	string.

     The gets()	function is equivalent to fgets() with an infinite size	and a
     stream of stdin, except that the newline character	(if any) is not	stored
     in	the string.  It	is the caller's	responsibility to ensure that the
     input line, if any, is sufficiently short to fit in the string.

RETURN VALUES
     Upon successful completion, fgets() and gets() return a pointer to	the
     string.  If end-of-file occurs before any characters are read, they
     return NULL and the buffer	contents remain	unchanged.  If an error
     occurs, they return NULL and the buffer contents are indeterminate.  The
     fgets() and gets()	functions do not distinguish between end-of-file and
     error, and	callers	must use feof(3) and ferror(3) to determine which
     occurred.

ERRORS
     [EBADF]		The given stream is not	a readable stream.

     The function fgets() may also fail	and set	errno for any of the errors
     specified for the routines	fflush(3), fstat(2), read(2), or malloc(3).

     The function gets() may also fail and set errno for any of	the errors
     specified for the routine getchar(3).

SECURITY CONSIDERATIONS
     The gets()	function cannot	be used	securely.  Because of its lack of
     bounds checking, and the inability	for the	calling	program	to reliably
     determine the length of the next incoming line, the use of	this function
     enables malicious users to	arbitrarily change a running program's func-
     tionality through a buffer	overflow attack.  It is	strongly suggested
     that the fgets() function be used in all cases.  (See the FSA.)

SEE ALSO
     feof(3), ferror(3), fgetln(3), fgetws(3)

     The FreeBSD Security Architecture.	 (See /usr/share/doc/{to be
     determined}.)

STANDARDS
     The functions fgets() and gets() conform to ISO/IEC 9899:1999
     (``ISO C99'').

FreeBSD	10.1			 June 4, 1993			  FreeBSD 10.1

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SECURITY CONSIDERATIONS | SEE ALSO | STANDARDS

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