from small one page howto to huge articles all in one place
 

search text in:





Poll
Which filesystem do you use?






poll results

Last additions:
using iotop to find disk usage hogs

using iotop to find disk usage hogs

words:

887

views:

90866

userrating:

average rating: 1.7 (82 votes) (1=very good 6=terrible)


May 25th. 2007:
Words

486

Views

206761

why adblockers are bad


Workaround and fixes for the current Core Dump Handling vulnerability affected kernels

Workaround and fixes for the current Core Dump Handling vulnerability affected kernels

words:

161

views:

88329

userrating:

average rating: 1.3 (28 votes) (1=very good 6=terrible)


April, 26th. 2006:

Druckversion
You are here: manpages





BIO_s_file

Section: OpenSSL (3)
Updated: 2015-01-20
Index Return to Main Contents
 

NAME

BIO_s_file, BIO_new_file, BIO_new_fp, BIO_set_fp, BIO_get_fp, BIO_read_filename, BIO_write_filename, BIO_append_filename, BIO_rw_filename - FILE bio  

SYNOPSIS

 #include <openssl/bio.h>

 BIO_METHOD *   BIO_s_file(void);
 BIO *BIO_new_file(const char *filename, const char *mode);
 BIO *BIO_new_fp(FILE *stream, int flags);

 BIO_set_fp(BIO *b,FILE *fp, int flags);
 BIO_get_fp(BIO *b,FILE **fpp);

 int BIO_read_filename(BIO *b, char *name)
 int BIO_write_filename(BIO *b, char *name)
 int BIO_append_filename(BIO *b, char *name)
 int BIO_rw_filename(BIO *b, char *name)

 

DESCRIPTION

BIO_s_file() returns the BIO file method. As its name implies it is a wrapper round the stdio FILE structure and it is a source/sink BIO.

Calls to BIO_read() and BIO_write() read and write data to the underlying stream. BIO_gets() and BIO_puts() are supported on file BIOs.

BIO_flush() on a file BIO calls the fflush() function on the wrapped stream.

BIO_reset() attempts to change the file pointer to the start of file using fseek(stream, 0, 0).

BIO_seek() sets the file pointer to position ofs from start of file using fseek(stream, ofs, 0).

BIO_eof() calls feof().

Setting the BIO_CLOSE flag calls fclose() on the stream when the BIO is freed.

BIO_new_file() creates a new file BIO with mode mode the meaning of mode is the same as the stdio function fopen(). The BIO_CLOSE flag is set on the returned BIO.

BIO_new_fp() creates a file BIO wrapping stream. Flags can be: BIO_CLOSE, BIO_NOCLOSE (the close flag) BIO_FP_TEXT (sets the underlying stream to text mode, default is binary: this only has any effect under Win32).

BIO_set_fp() set the fp of a file BIO to fp. flags has the same meaning as in BIO_new_fp(), it is a macro.

BIO_get_fp() retrieves the fp of a file BIO, it is a macro.

BIO_seek() is a macro that sets the position pointer to offset bytes from the start of file.

BIO_tell() returns the value of the position pointer.

BIO_read_filename(), BIO_write_filename(), BIO_append_filename() and BIO_rw_filename() set the file BIO b to use file name for reading, writing, append or read write respectively.  

NOTES

When wrapping stdout, stdin or stderr the underlying stream should not normally be closed so the BIO_NOCLOSE flag should be set.

Because the file BIO calls the underlying stdio functions any quirks in stdio behaviour will be mirrored by the corresponding BIO.

On Windows BIO_new_files reserves for the filename argument to be UTF-8 encoded. In other words if you have to make it work in multi- lingual environment, encode file names in UTF-8.  

EXAMPLES

File BIO ``hello world'':

 BIO *bio_out;
 bio_out = BIO_new_fp(stdout, BIO_NOCLOSE);
 BIO_printf(bio_out, "Hello World\n");

Alternative technique:

 BIO *bio_out;
 bio_out = BIO_new(BIO_s_file());
 if(bio_out == NULL) /* Error ... */
 if(!BIO_set_fp(bio_out, stdout, BIO_NOCLOSE)) /* Error ... */
 BIO_printf(bio_out, "Hello World\n");

Write to a file:

 BIO *out;
 out = BIO_new_file("filename.txt", "w");
 if(!out) /* Error occurred */
 BIO_printf(out, "Hello World\n");
 BIO_free(out);

Alternative technique:

 BIO *out;
 out = BIO_new(BIO_s_file());
 if(out == NULL) /* Error ... */
 if(!BIO_write_filename(out, "filename.txt")) /* Error ... */
 BIO_printf(out, "Hello World\n");
 BIO_free(out);

 

RETURN VALUES

BIO_s_file() returns the file BIO method.

BIO_new_file() and BIO_new_fp() return a file BIO or NULL if an error occurred.

BIO_set_fp() and BIO_get_fp() return 1 for success or 0 for failure (although the current implementation never return 0).

BIO_seek() returns the same value as the underlying fseek() function: 0 for success or -1 for failure.

BIO_tell() returns the current file position.

BIO_read_filename(), BIO_write_filename(), BIO_append_filename() and BIO_rw_filename() return 1 for success or 0 for failure.  

BUGS

BIO_reset() and BIO_seek() are implemented using fseek() on the underlying stream. The return value for fseek() is 0 for success or -1 if an error occurred this differs from other types of BIO which will typically return 1 for success and a non positive value if an error occurred.  

SEE ALSO

BIO_seek(3), BIO_tell(3), BIO_reset(3), BIO_flush(3), BIO_read(3), BIO_write(3), BIO_puts(3), BIO_gets(3), BIO_printf(3), BIO_set_close(3), BIO_get_close(3)


 

Index

NAME
SYNOPSIS
DESCRIPTION
NOTES
EXAMPLES
RETURN VALUES
BUGS
SEE ALSO


Please read "Why adblockers are bad".



Other free services
toURL.org
Shorten long
URLs to short
links like
http://tourl.org/2
tourl.org
.
Reverse DNS lookup
Find out which hostname(s)
resolve to a
given IP or other hostnames for the server
www.reversednslookup.org
rdf newsfeed | rss newsfeed | Atom newsfeed
- Powered by LeopardCMS - Running on Gentoo -
Copyright 2004-2013 Sascha Nitsch Unternehmensberatung UG(haftungsbeschränkt)
Valid XHTML1.1 : Valid CSS : buttonmaker
- Level Triple-A Conformance to Web Content Accessibility Guidelines 1.0 -
- Copyright and legal notices -
Time to create this page: 3.4 ms