Logstash not able to read input file

I have following code.
input {
file {
path => "C:\logstash-7.2.0\samples\test_10.log"
start_position => "beginning"
ignore_older => 0
}
}

filter {

}

output {
stdout { codec => rubydebug}
}

I ran in debug mode after deleting sincedb file from default location.
I am constantly getting following message in the log files:
[2019-07-30T21:59:19,509][DEBUG][logstash.instrument.periodicpoller.cgroup] One or more required cgroup files or directories not found: /proc/self/cgroup, /sys/fs/cgroup/cpuacct, /sys/fs/cgroup/cpu
[2019-07-30T21:59:19,722][DEBUG][logstash.instrument.periodicpoller.jvm] collector name {:name=>"ParNew"}
[2019-07-30T21:59:19,723][DEBUG][logstash.instrument.periodicpoller.jvm] collector name {:name=>"ConcurrentMarkSweep"}
[2019-07-30T21:59:21,970][DEBUG][org.logstash.execution.PeriodicFlush] Pushing flush onto pipeline.

Run in TRACE mode. The file input will log more info on what decisions it is making when it "discovers" the file.

Do not use backslash in the path option of a file input, use forward slash.

THanks both of you. I implemented both the suggestions and getting follows:

[2019-07-31T09:46:54,623][TRACE][filewatch.sincedbcollection] associate: finding {"inode"=>"3054569709-95108-11403264", "path"=>"C:/logstash-7.2.0/samples/test_10.log"}
[2019-07-31T09:46:54,629][TRACE][filewatch.sincedbcollection] associate: unmatched
[2019-07-31T09:46:54,647][TRACE][filewatch.discoverer ] Discoverer discover_files: C:/logstash-7.2.0/samples/test_10.log: skipping because it was last modified more than 0.0 seconds ago

Not able to understand the disconnect. I am deleteing the sincedb file before every run.

I commented out ignore_older => 0 and got it working.