Is there a way to check for a file with specific name with ros?

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Hi. Sorry for all mistakes, English is not my native language. I have a node that writes data in file and name of that file is "pose.csv". I need to make sure that every time I start that node it writes data in new file, so result is should be like then I start node first time it loads data in file "pose_1.csv", than I started it second time the file should be "pose2.csv". Is there a way to achieve this using ros. As far as I know there is no way to check, how many times node has been run, but I could be wrong. Appreciate any help.