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   getpass    ( 3 )

получить пароль (get a password)

Имя (Name)

getpass - get a password

Синопсис (Synopsis)

#include <unistd.h>

char *getpass(const char *prompt);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

getpass(): Since glibc 2.2.2: _XOPEN_SOURCE && ! (_POSIX_C_SOURCE >= 200112L) || /* Glibc since 2.19: */ _DEFAULT_SOURCE || /* Glibc <= 2.19: */ _BSD_SOURCE Before glibc 2.2.2: none


Описание (Description)

This function is obsolete.  Do not use it.  If you want to read
       input without terminal echoing enabled, see the description of
       the ECHO flag in termios(3).

The getpass() function opens /dev/tty (the controlling terminal of the process), outputs the string prompt, turns off echoing, reads one line (the "password"), restores the terminal state and closes /dev/tty again.


Возвращаемое значение (Return value)

The function getpass() returns a pointer to a static buffer
       containing (the first PASS_MAX bytes of) the password without the
       trailing newline, terminated by a null byte ('\0').  This buffer
       may be overwritten by a following call.  On error, the terminal
       state is restored, errno is set to indicate the error, and NULL
       is returned.

Ошибки (Error)

ENXIO  The process does not have a controlling terminal.

Файлы (Files)

/dev/tty

Атрибуты (Attributes)

For an explanation of the terms used in this section, see
       attributes(7).

┌───────────────────────────────┬───────────────┬────────────────┐ │Interface Attribute Value │ ├───────────────────────────────┼───────────────┼────────────────┤ │getpass() │ Thread safety │ MT-Unsafe term │ └───────────────────────────────┴───────────────┴────────────────┘


Стандарты (Conforming to)

Present in SUSv2, but marked LEGACY.  Removed in POSIX.1-2001.

Примечание (Note)

In the GNU C library implementation, if /dev/tty cannot be
       opened, the prompt is written to stderr and the password is read
       from stdin.  There is no limit on the length of the password.
       Line editing is not disabled.

According to SUSv2, the value of PASS_MAX must be defined in <limits.h> in case it is smaller than 8, and can in any case be obtained using sysconf(_SC_PASS_MAX). However, POSIX.2 withdraws the constants PASS_MAX and _SC_PASS_MAX, and the function getpass(). The glibc version accepts _SC_PASS_MAX and returns BUFSIZ (e.g., 8192).


Ошибки (баги) (Bugs)

The calling process should zero the password as soon as possible
       to avoid leaving the cleartext password visible in the process's
       address space.

Смотри также (See also)

crypt(3)