получить строку из потока стандартного ввода (get a string from a stdin stream)
Пролог (Prolog)
This manual page is part of the POSIX Programmer's Manual. The
Linux implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
Имя (Name)
gets — get a string from a stdin stream
Синопсис (Synopsis)
#include <stdio.h>
char *gets(char *s);
Описание (Description)
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 POSIX.1‐2017 defers to the ISO C standard.
The gets() function shall read bytes from the standard input
stream, stdin, into the array pointed to by s, until a <newline>
is read or an end-of-file condition is encountered. Any <newline>
shall be discarded and a null byte shall be placed immediately
after the last byte read into the array.
The gets() function may mark the last data access timestamp of
the file associated with stream for update. The last data access
timestamp shall be marked for update by the first successful
execution of fgetc(), fgets(), fread(), fscanf(), getc(),
getchar(), getdelim(), getline(), gets(), or scanf() using stream
that returns data not supplied by a prior call to ungetc().
Возвращаемое значение (Return value)
Upon successful completion, gets() shall return s. If the end-
of-file indicator for the stream is set, or if the stream is at
end-of-file, the end-of-file indicator for the stream shall be
set and gets() shall return a null pointer. If a read error
occurs, the error indicator for the stream shall be set, gets()
shall return a null pointer, and set errno to indicate the error.
Ошибки (Error)
Refer to fgetc(3p).
The following sections are informative.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
Reading a line that overflows the array pointed to by s results
in undefined behavior. The use of fgets() is recommended.
Since the user cannot specify the length of the buffer passed to
gets(), use of this function is discouraged. The length of the
string read is unlimited. It is possible to overflow this buffer
in such a way as to cause applications to fail, or possible
system security violations.
Applications should use the fgets() function instead of the
obsolescent gets() function.
Обоснование (Rationale)
The standard developers decided to mark the gets() function as
obsolescent even though it is in the ISO C standard due to the
possibility of buffer overflow.
Будущие направления (Future directions)
The gets() function may be removed in a future version.
Смотри также (See also)
Section 2.5, Standard I/O Streams, feof(3p), ferror(3p),
fgets(3p)
The Base Definitions volume of POSIX.1‐2017, stdio.h(0p)
