text: READPASSPHRASE(3) BSD Programmer's Manual READPASSPHRASE(3)
  readpassphrase - get a passphrase from the user
  #include <readpassphrase.h> char * readpassphrase(const char *prompt, char *buf, size_t bufsiz, int flags);
  The. readpassphrase() RPP_STDIN force read of passphrase from stdin The calling process should zero the passphrase as soon as possible to avoid leaving the cleartext passphrase visible in the process's address space.
  Upon successful completion, readpassphrase() returns a pointer to the NUL-terminated passphrase. If an error is encountered, the terminal state is restored and a null pointer is returned.
  /dev/tty));
  [EINTR] The readpassphrase() function was interrupted by a signal. [EINVAL] The bufsiz argument was zero. [EIO] The process is a member of a background process attempting to read from its controlling terminal, the process is ig- noring.() was called, that handler is then executed. If no handler was previously installed for the signal then the default action is taken as per sigaction(2). The SIGTSTP, SIGTTIN, and SIGTTOU signals (stop signals generated from keyboard or due to terminal I/O from a background process) are treated specially. When the process is resumed after it has been stopped, 28,.