BIO_s_fd, BIO_set_fd, BIO_get_fd, BIO_new_fd - File
descriptor BIO
#include <openssl/bio.h>
BIO_METHOD * BIO_s_fd(
void ); #define
BIO_set_fd(b,fd,c) BIO_int_ctrl(b,BIO_C_SET_FD,c,fd)
#define BIO_get_fd(b,c) BIO_ctrl(b,BIO_C_GET_FD,0,(char
*)c)
BIO *BIO_new_fd(
int fd,
int close_flag );
The BIO_s_fd() function returns the file descriptor BIO
method. This is a wrapper around the platform's file
descriptor routines, such as read() and write().
The BIO_read() and BIO_write() functions read or write the
underlying descriptor. BIO_puts() is supported, but
BIO_gets() is not.
If the close flag is set then then close() is called on
the underlying file descriptor when the BIO is freed.
The BIO_reset() function attempts to change the file
pointer to the start of file using lseek(fd, 0, 0).
The BIO_seek() function sets the file pointer to position
ofs from start of file using lseek(fd, ofs, 0).
The BIO_tell() function returns the current file position
by calling lseek(fd, 0, 1).
The BIO_set_fd() function sets the file descriptor of BIO
b to fd and the close flag to c.
The BIO_get_fd() function places the file descriptor in c
if it is not NULL. It also returns the file descriptor.
If c is not NULL it should be of type (int *).
The BIO_new_fd() function returns a file descriptor BIO
using fd and close_flag.
The behavior of the BIO_read() and BIO_write() functions
depends on the behavior of the platform's read() and
write() calls on the descriptor. If the underlying file
descriptor is in a nonblocking mode then the BIO will
behave in the manner described in the BIO_read(3) and
BIO_should_retry(3) reference pages.
File descriptor BIOs should not be used for socket I/O.
Use socket BIOs instead.
BIO_s_fd() returns the file descriptor BIO method.
BIO_reset() returns zero for success and -1 if an error
occurred. BIO_seek() and BIO_tell() return the current
file position or -1 is an error occurred. These values
reflect the underlying lseek() behavior.
BIO_set_fd() always returns 1.
BIO_get_fd() returns the file descriptor or -1 if the BIO
has not been initialized.
BIO_new_fd() returns the newly allocated BIO or NULL is an
error occurred.
This is a file descriptor BIO version of "Hello World":
BIO *out; out = BIO_new_fd(fileno(stdout), BIO_NOCLOSE);
BIO_printf(out, "Hello World\n"); BIO_free(out);
Functions: BIO_seek(3), BIO_tell(3), BIO_reset(3),
BIO_read(3), BIO_write(3), BIO_puts(3), BIO_gets(3),
BIO_printf(3), BIO_set_close(3), BIO_get_close(3)
BIO_s_fd(3)
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