xpdf:tldr:6e68d

The command xpdf -z ${select} ${filename-pdf} is used to open a PDF file named ${filename-pdf} with the xpdf program, zoomed in or out depending on the ${select} value.

Here is the breakdown of the command:

• xpdf: This is the name of the command-line PDF viewer.
• -z: This option instructs xpdf to zoom in or out on the PDF file.
• ${select}: This variable should contain a zoom level value. Depending on the value specified, the PDF will either be zoomed in or out to the desired level.
• ${filename-pdf}: This variable should contain the name of the PDF file to be opened by xpdf.

In summary, by running this command, the xpdf program will be launched, and the specified PDF file will be opened with a zoom level determined by the ${select} value.