# SLOG_Irec_FromInputStream

Return a pointer to the next interval record in the given SLOG_STREAM. The interval record returned can be real or pseudo record.

## Synopsis

    const SLOG_intvlrec_t *
    SLOG_Irec_FromInputStream( SLOG_STREAM *slog, int *irc )

## Modified Input Variables

slog - pointer to the SLOG_STREAM where interval record is retrieved.

irc - pointer to the returned integer status code.

## Modified Output Variables

returned value - pointer to the next interval record of type SLOG_intvlrec_t in the frame buffer. The "const" qualifier indicates that user should NOT modify the content. The pointer is NULL when the routine encounters error or end of file.

## Usage Notes on this subroutine

The routine returns a pointer to the interval record of the various Bbuf in current frame buffer in the SLOG_STREAM given. The routine does NOT create new node/irec. It just simply returns a pointer to the existing one in the bi-directional linked list( an internal data structure ). If one wants to modify the content of the interval record without modification of the specified bi-directional linked node, one should use SLOG_Irec_Copy() to copy the returned record content to a new record. The routine also ADVANCES the internal pointer of the specified linked list buffer. Also, the routine does NOT gurantee the memory associated with previously _returned_ interval record be retained in the next call of the routine. So if one wants to keep interval record for future reference, one need to use SLOG_Irec_Copy() to copy the content of the interval record to another memory location __BEFORE__ calling SLOG_Irec_FromInputStream() again. The example program, slog_readtest.c shows the typical way of using this subroutine.

## Include File Needed

slog.h

## Notes on SLOG return status code

There are 5 allowed SLOG returned status codes. They include SLOG_SUCCESS, SLOG_FAIL and SLOG_EOF. Their actual values are defined in slog.h

SLOG_SUCCESS is returned when no error is encountered.

SLOG_FAIL is returned when error is encounted.

SLOG_EOF is returned when End of file is encounted.

There are also SLOG_TRUE and SLOG_FALSE which are sued as boolean values, in particular they are used in boolean functions which are usually named as IsXXXXX(), AreXXXXX() and HasXXXXX().

Location:../src/slog_irec_read.c