SEQ_OPEN(9) The Linux VFS SEQ_OPEN(9)NAME
seq_open - initialize sequential file
SYNOPSIS
int seq_open(struct file * file, const struct seq_operations * op);
ARGUMENTS
file
file we initialize
op
method table describing the sequence
DESCRIPTION
seq_open sets file, associating it with a sequence described by op. op->start sets the iterator up and returns the first element of
sequence. op->stop shuts it down. op->next returns the next element of sequence. op->show prints element into the buffer. In case of
error ->start and ->next return ERR_PTR(error). In the end of sequence they return NULL. ->show returns 0 in case of success and negative
number in case of error. Returning SEQ_SKIP means "discard this element and move on".
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 SEQ_OPEN(9)
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ICONV(3) Linux Programmer's Manual ICONV(3)NAME
iconv - perform character set conversion
SYNOPSIS
#include <iconv.h>
size_t iconv(iconv_t cd,
char **inbuf, size_t *inbytesleft,
char **outbuf, size_t *outbytesleft);
DESCRIPTION
The argument cd must be a conversion descriptor created using the function iconv_open.
The main case is when inbuf is not NULL and *inbuf is not NULL. In this case, the iconv function converts the multibyte sequence starting
at *inbuf to a multibyte sequence starting at *outbuf. At most *inbytesleft bytes, starting at *inbuf, will be read. At most *out-
bytesleft bytes, starting at *outbuf, will be written.
The iconv function converts one multibyte character at a time, and for each character conversion it increments *inbuf and decrements
*inbytesleft by the number of converted input bytes, it increments *outbuf and decrements *outbytesleft by the number of converted output
bytes, and it updates the conversion state contained in cd. The conversion can stop for four reasons:
1. An invalid multibyte sequence is encountered in the input. In this case it sets errno to EILSEQ and returns (size_t)(-1). *inbuf is left
pointing to the beginning of the invalid multibyte sequence.
2. The input byte sequence has been entirely converted, i.e. *inbytesleft has gone down to 0. In this case iconv returns the number of non-
reversible conversions performed during this call.
3. An incomplete multibyte sequence is encountered in the input, and the input byte sequence terminates after it. In this case it sets
errno to EINVAL and returns (size_t)(-1). *inbuf is left pointing to the beginning of the incomplete multibyte sequence.
4. The output buffer has no more room for the next converted character. In this case it sets errno to E2BIG and returns (size_t)(-1).
A different case is when inbuf is NULL or *inbuf is NULL, but outbuf is not NULL and *outbuf is not NULL. In this case, the iconv function
attempts to set cd's conversion state to the initial state and store a corresponding shift sequence at *outbuf. At most *outbytesleft
bytes, starting at *outbuf, will be written. If the output buffer has no more room for this reset sequence, it sets errno to E2BIG and
returns (size_t)(-1). Otherwise it increments *outbuf and decrements *outbytesleft by the number of bytes written.
A third case is when inbuf is NULL or *inbuf is NULL, and outbuf is NULL or *outbuf is NULL. In this case, the iconv function sets cd's
conversion state to the initial state.
RETURN VALUE
The iconv function returns the number of characters converted in a non-reversible way during this call; reversible conversions are not
counted. In case of error, it sets errno and returns (size_t)(-1).
ERRORS
The following errors can occur, among others:
E2BIG There is not sufficient room at *outbuf.
EILSEQ An invalid multibyte sequence has been encountered in the input.
EINVAL An incomplete multibyte sequence has been encountered in the input.
CONFORMING TO
UNIX98
SEE ALSO iconv_open(3), iconv_close(3)GNU 2001-11-15 ICONV(3)