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2 .\" The Regents of the University of California. All rights reserved.
4 .\" This code is derived from software contributed to Berkeley by
5 .\" Chris Torek and the American National Standards Committee X3,
6 .\" on Information Processing Systems.
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36 .\" @(#)fgets.3 8.1 (Berkeley) 6/4/93
45 .Nd get a line from a stream
51 .Fn fgets "char *str" "int size" "FILE *stream"
58 reads at most one less than the number of characters specified by
62 and stores them in the string
64 Reading stops when a newline character is found,
65 at end-of-file or error.
66 The newline, if any, is retained.
67 If any characters are read and there is no error, a
69 character is appended to end the string.
82 except that the newline character (if any) is not stored in the string.
83 It is the caller's responsibility to ensure that the input line,
84 if any, is sufficiently short to fit in the string.
86 Upon successful completion,
91 a pointer to the string.
92 If end-of-file occurs before any characters are read,
95 and the buffer contents remain unchanged.
99 and the buffer contents are indeterminate.
105 do not distinguish between end-of-file and error, and callers must use
109 to determine which occurred.
115 is not a readable stream.
120 may also fail and set
122 for any of the errors specified for the routines
131 may also fail and set
133 for any of the errors specified for the routine
135 .Sh SECURITY CONSIDERATIONS
138 function cannot be used securely.
139 Because of its lack of bounds checking,
140 and the inability for the calling program
141 to reliably determine the length of the next incoming line,
142 the use of this function enables malicious users
143 to arbitrarily change a running program's functionality through
144 a buffer overflow attack.
145 It is strongly suggested that the
147 function be used in all cases.
155 .%T "The FreeBSD Security Architecture"
158 .Pa /usr/share/doc/{to be determined} . )