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author | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2012-08-02 18:43:01 +0000 |
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committer | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2012-08-02 18:43:01 +0000 |
commit | b7ab7f5ea41b6b230e133e1c847dbbfc2d8ee421 (patch) | |
tree | 7a15a85d8ea3a21cc51f140ac702f9c613df0c66 /nuttx/drivers/syslog/README.txt | |
parent | 91bc37410bc27d9d3c1c880e783f26f748f2e434 (diff) | |
download | px4-nuttx-b7ab7f5ea41b6b230e133e1c847dbbfc2d8ee421.tar.gz px4-nuttx-b7ab7f5ea41b6b230e133e1c847dbbfc2d8ee421.tar.bz2 px4-nuttx-b7ab7f5ea41b6b230e133e1c847dbbfc2d8ee421.zip |
Fix syslog mutual exclusion and interrupt level logic
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4999 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/drivers/syslog/README.txt')
-rw-r--r-- | nuttx/drivers/syslog/README.txt | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/nuttx/drivers/syslog/README.txt b/nuttx/drivers/syslog/README.txt index 611f43567..bfef73ae8 100644 --- a/nuttx/drivers/syslog/README.txt +++ b/nuttx/drivers/syslog/README.txt @@ -14,10 +14,16 @@ syslog_putc(). One version of syslog_putc() is defined in fs/fs_syslog.c; that version is used when CONFIG_SYSLOG_CHAR is defined. That version of syslog_putc() just integrates with the file system to re-direct debug output to a -character device or to a file. +character device or to a file. A disadvantage of using the generic character +device for the SYSLOG is that it cannot handle debug output generated from +interrupt level handles. If CONFIG_SYSLOG_CHAR is not defined, then other custom SYSLOG drivers -can be used. Those custom SYSLOG drivers reside in this directory. +can be used. These custom SYSLOG drivers can do things like handle +unusual logging media and since they can avoid the general file system +interfaces, can be designed to support debug output from interrupt handlers. + +Those custom SYSLOG drivers reside in this directory. ramlog.c -------- @@ -46,7 +52,9 @@ ramlog.c interface. If this feature is enabled (along with CONFIG_SYSLOG), then all debug output (only) will be re-directed to the circular buffer in RAM. This RAM log can be view from NSH using the 'dmesg' - command. + command. NOTE: Unlike the limited, generic character driver SYSLOG + device, the RAMLOG *can* be used to generate debug output from interrupt + level handlers. CONFIG_RAMLOG_NPOLLWAITERS - The number of threads than can be waiting for this driver on poll(). Default: 4 |