[SOLVED] UNIX split command splitting this file, but what names are resulting?

Issue

We receive a big csv file from a client (500k lines, est) that we split into smaller chunks using the split command.

You can see how we're using the command below, but my bash knowledge is a bit rusty, could someone refresh me on the ${processFile}_ bit below, and how the files are being named in the end? Not recalling what the underscore does...

split -l 50000 $PROCESSING_CURRENT_DIR/$processFile ${processFile}_

Solution

This isn't anything to do with bash but how split(1) command processes its arguments to split the input.

Syntax is:

   split [OPTION]... [FILE [PREFIX]]

DESCRIPTION Output pieces of FILE to PREFIXaa, PREFIXab, ...; default size is 1000 lines, and default PREFIX is 'x'.

   With no FILE, or when FILE is -, read standard input.

So it uses the given prefix and makes output files.

Answered By - P.P