1 .\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
3 .\" %%%LICENSE_START(VERBATIM)
4 .\" Permission is granted to make and distribute verbatim copies of this
5 .\" manual provided the copyright notice and this permission notice are
6 .\" preserved on all copies.
8 .\" Permission is granted to copy and distribute modified versions of this
9 .\" manual under the conditions for verbatim copying, provided that the
10 .\" entire resulting derived work is distributed under the terms of a
11 .\" permission notice identical to this one.
13 .\" Since the Linux kernel and libraries are constantly changing, this
14 .\" manual page may be incorrect or out-of-date. The author(s) assume no
15 .\" responsibility for errors or omissions, or for damages resulting from
16 .\" the use of the information contained herein. The author(s) may not
17 .\" have taken the same level of care in the production of this manual,
18 .\" which is licensed free of charge, as they might when working
21 .\" Formatted or processed versions of this manual, if unaccompanied by
22 .\" the source, must acknowledge the copyright and authors of this work.
25 .\" Modified Wed Jul 28 11:12:07 1993 by Rik Faith (faith@cs.unc.edu)
26 .\" Modified Fri Sep 8 15:48:13 1995 by Andries Brouwer (aeb@cwi.nl)
27 .TH GETS 3 2012-01-18 "GNU" "Linux Programmer's Manual"
29 fgetc, fgets, getc, getchar, gets, ungetc \- input of characters and strings
34 .BI "int fgetc(FILE *" stream );
36 .BI "char *fgets(char *" "s" ", int " "size" ", FILE *" "stream" );
38 .BI "int getc(FILE *" stream );
40 .B "int getchar(void);"
42 .BI "char *gets(char *" "s" );
44 .BI "int ungetc(int " c ", FILE *" stream );
48 reads the next character from
56 on end of file or error.
61 except that it may be implemented as a macro which evaluates
67 .BI "getc(" stdin ) \fR.
72 into the buffer pointed to by
74 until either a terminating newline or
76 which it replaces with a null byte (\(aq\e0\(aq).
77 No check for buffer overrun is performed (see BUGS below).
80 reads in at most one less than
84 and stores them into the buffer pointed to by
86 Reading stops after an
89 If a newline is read, it is stored into the buffer.
90 A terminating null byte (\(aq\e0\(aq)
91 is stored after the last character in the buffer.
100 where it is available for subsequent read operations.
101 Pushed-back characters
102 will be returned in reverse order; only one pushback is guaranteed.
104 Calls to the functions described here can be mixed with each other and with
105 calls to other input functions from the
107 library for the same input stream.
109 For nonlocking counterparts, see
110 .BR unlocked_stdio (3).
116 return the character read as an
122 on end of file or error.
130 on error or when end of file occurs while no characters have been read.
139 C89, C99, POSIX.1-2001.
146 ISO C11 removes the specification of
148 from the C language, and since version 2.16,
149 glibc header files don't expose the function declaration if the
151 feature test macro is defined.
155 Because it is impossible to tell without knowing the data in advance how many
158 will read, and because
160 will continue to store characters past the end of the buffer,
161 it is extremely dangerous to use.
162 It has been used to break computer security.
167 It is not advisable to mix calls to input functions from the
169 library with low-level calls to
171 for the file descriptor associated with the input stream; the results
172 will be undefined and very probably not what you want.
187 .BR unlocked_stdio (3),
188 .BR feature_test_macros (7)