RTOS/rtems
1
0
Fork 0
forked from Imagelibrary/rtems
Code Pull Requests Activity

Reviewed log_read().

Browse Source
This commit is contained in:
Joel Sherrill
1998-08-28 19:59:44 +00:00
parent 566669f5f1
commit 82db2d3ade
1 changed files with 40 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

60
doc/new_chapters/eventlog.t
View File

@@ -23,7 +23,7 @@ The directives provided by the event logging manager are:
@item @code{log_write_any} - Write to any log file @item @code{log_write_any} - Write to any log file
@item @code{log_write_entry} - Write entry to any log file @item @code{log_write_entry} - Write entry to any log file
@item @code{log_open} - Open a log file @item @code{log_open} - Open a log file
@item @code{log_read} - Read from the system Log @item @code{log_read} - Read from a log file
@item @code{log_notify} - Notify Process of writes to the system log @item @code{log_notify} - Notify Process of writes to the system log
@item @code{log_close} - Close log descriptor @item @code{log_close} - Close log descriptor
@item @code{log_seek} - Reposition log file offset @item @code{log_seek} - Reposition log file offset
@@ -462,7 +462,7 @@ should actually be detected by @code{open} and passed back by the
and @code{ENOTDIR} are detected in this manner. and @code{ENOTDIR} are detected in this manner.
@page @page
@subsection log_read - Read from the system Log @subsection log_read - Read from a log file
@subheading CALLING SEQUENCE: @subheading CALLING SEQUENCE:
@@ -486,13 +486,22 @@ int log_read(
@subheading STATUS CODES: @subheading STATUS CODES:
@table @b @table @b
@item E2BIG
This error indicates an inconsistency in the implementation.
Report this as a bug.
@item EBADF @item EBADF
The logdes argument is not a valid log file descriptor. The @code{logdes} argument is not a valid log file descriptor.
@item EFAULT
The @code{entry} argument is not a valid pointer to a log entry structure.
@item EFAULT
The @code{log_sizeread} argument is not a valid pointer to a size_t.
@item EBUSY @item EBUSY
No data available. The open log file descriptor references No data available. There are no unread event records remaining
the current system log. and there are no unread event records in this log file.
remaining.
@item EINTR @item EINTR
A signal interrupted the call to log_read(). A signal interrupted the call to log_read().
@@ -500,30 +509,34 @@ A signal interrupted the call to log_read().
@item EIO @item EIO
An I/O error occurred in reading from the event log. An I/O error occurred in reading from the event log.
@item EINVAL
The matching event record has data associated with it and
@code{log_buf} was not a valid pointer.
@item EINVAL
The matching event record has data associated with it which is
longer than @code{log_len}.
@end table @end table
@subheading DESCRIPTION: @subheading DESCRIPTION:
The @code{log_read} function shall attempt to read the @code{log_entry} The @code{log_read} function reads the @code{log_entry}
structure and @code{log_len} bytes of data from the next event record structure and up to @code{log_len} bytes of data from the next
of the log file associated with the open log file descriptor @code{logdes}, event record of the log file associated with the open log file
placing the @code{log_entry} structure into the buffer pointed to by descriptor @code{logdes}. The event record read is placed
@code{entry}, and the data into the buffer pointed to by @code{log_buf}. into the @code{log_entry} structure pointed to by
The log record ID of the returned event record shall be stored in the @code{entry} and any data into the buffer pointed to by @code{log_buf}.
The log record ID of the returned event record is be stored in the
@code{log_recid} member of the @code{log_entry} structure for the event @code{log_recid} member of the @code{log_entry} structure for the event
record. record.
If the query attribute of the open log file description associated with If the query attribute of the open log file description associated with
the @code{logdes} is set, the event record read shall match that query. the @code{logdes} is set, the event record read will match that query.
If the @code{entry} argument is not NULL it will point to a @code{log_entry}
structure which shall be filled with the creation information for this log
entry. If the argument @code{log_buf} is not NULL the data written with the
log entry will be placed in the buffer. The size of the buffer is specified
by the argument @code{log_len}.
If the @code{log_read} is successful the call shall store the actual length If the @code{log_read} is successful the call stores the actual length
of the data associated with the event record into the location specified by of the data associated with the event record into the location specified by
@code{log_sizeread}. This number may be smaller or greater than @code{log_sizeread}. This number will be less than or equal to
@code{log_len}. @code{log_len}.
@subheading NOTES: @subheading NOTES:
@@ -531,6 +544,13 @@ of the data associated with the event record into the location specified by
The @code{_POSIX_LOGGING} feature flag is defined to indicate The @code{_POSIX_LOGGING} feature flag is defined to indicate
this service is available. this service is available.
When @code{EINVAL} is returned, then no data is returned although the
event record is returned. This is an extension to the POSIX specification.
The POSIX specification specifically allows @code{log_read} to write
greater than @code{log_len} bytes into @code{log_buf}. This is highly
undesirable and this implementation will NOT do this.
@page @page
@subsection log_notify - Notify Process of writes to the system log. @subsection log_notify - Notify Process of writes to the system log.