Solaris Logs – How to Less a Filename Rather Than an Inode Number

lesslogssolaristail

I have a piece of software that rotates its log files when it restarts. However, during development, I am restarting it a lot, so I would like to monitor the latest log file at any time.

If I start less normally with less program.log and hit Shift+f to tail, when the log file is rotated, I carry on monitoring the old log file. I assume this is because the inode number stays the same and less has an open file handle to that inode.

Is it possible to monitor the latest activity on whatever log file is currently called program.log?

Specifically, I am working on Sun OS, so a solution that works there would be ideal.

Best Answer

Use less --follow-name if your version of less supports it.
That option was introduced in version 416.

Then do a normal follow command Shift+F within less.

Related Solutions

Is it fine to use tail -f on large log files

On my linux system (GNU coreutils 8.12), I was able to check (using strace) that tail -f¹ uses the lseek system call to skip over most of the file quickly:

lseek(3, 0, SEEK_CUR)                   = 0
lseek(3, 0, SEEK_END)                   = 194086
lseek(3, 188416, SEEK_SET)              = 188416

This means that the size of the tracked file should not matter in anyway.

Maybe you can check if the same applies on your system. (Obviously, it should be the case.)

—
^{1. I also tried disabling inotify support with the undocumented ---disable-inotify, just in case.}

Linux – Get ‘less’ to display filename

Why pipe less into anything? That turns it into cat. The obvious answer is

grep some_var * | less

You'll get output of the form

filename:this line contains some_var somewhere

If you pass the option -n to grep, you also get line numbers:

filename:42:this line contains some_var somewhere

Many editors have some form of file search built in, with the search results appearing in a window where you can select a line to open the corresponding file at the corresponding location. In Emacs, run M-x grep or one of its variants. In Vim, run :grep or one of its variants.

Best Answer

Related Solutions

Is it fine to use tail -f on large log files

Linux – Get ‘less’ to display filename

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