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App-Prefix-0.10
River stage zero No dependents
/ prefix

NAME

prefix - prefixes hostname time information or more to lines from stdin (or read from files)

SYNOPSIS

    % tail -f /var/log/some.log | prefix -host -timestamp

tails a file, showing each line with a hostname and a timestamp like. So if we were tailing a growing file with lines like:

    OK: System operational
    Warning: Disk bandwidth saturated

we would get real-time output like:

    host.example.com 2013-10-13 16:51:26 OK: System operational
    host.example.com 2013-10-13 16:55:47 Warning: Disk bandwidth saturated
    host.example.com 2013-10-13 16:55:49 Warning: Things are wonky: disks spinning backwards
    host.example.com 2013-10-13 16:55:50 Error: Data read wackbards
    host.example.com 2013-10-13 16:56:10 OK: Spacetime reversal complete

Note that the hostname (host.example.com) and the date have been prepended to the lines from the file

DESCRIPTION

A text filter that prepends (or appends) data to lines read from stdin or named files, and echos them to stdout

OPTIONS

--text='arbitrary text here'

add any particular string you like. For example

    % ./some_program | prefix -text="TestRun17:" -utime > logfile.txt

The above example would prefix each line output from some_program with the time and the text 'TestRun17:' (without the quotes).

--timestamp

Add a timestamp to each line

--utimestamp

Add a timestamp, showing fractions of a second to each line

Example:

    % ls -l | prefix -timestamp

--hoststamp

Add the hostname to each line

--no-space

Don't put a space between the original line read and the data added to each line

--suffix

Show added data at end of line, not start of line

For example:

    % echo "abc" | prefix -suffix -text=:Run17:

will output

    abc "Run17:

whereas:

    % echo "abc" | prefix -text=:Run17:

would output

    :Run17: abc

--elapsed

Show time elapsed since last line seen. Shows fractional time.

--quote

Show each original line read in single quotes

AUTHOR

Josh Rabinowitz <joshr>