# Command: veritas¶

## COMMAND¶

veritas – validate that a Humdrum document has not been modified

## SYNOPSIS¶

 veritas [-v] inputfile

## DESCRIPTION¶

The veritas command provides an on-line means for formally or informally verifying that a given Humdrum file originates with a given publisher or source, or whether the file has been modified in some way. The command provides a convenient way of reassuring scholars of the accuracy or origin of a document.

The veritas command looks for a checksum validation number encoded in a VTS reference record in the given input file. (See the **Reference Records (1)** description.) The command then calculates the checksum for the file (excluding the VTS record itself) and compares this value with the checksum encoded in the file. If these values differ, a warning is issued that the file has been modified in some way. If these values are the same, a confirming message is issued.

Note that this verification process is easily circumvented by malicious individuals. For better security, the -v option should be invoked and the output checksum value should be compared with an independent printed list of checksums provided by the supplier of the electronic document.

## OPTIONS¶

The veritas command provides the following options:

 -h displays a help screen summarizing the command syntax -v invoke verbose mode

Options are specified in the command line.

The -v option will cause the checksum validation number to be output. This value should be manually compared with a printed checksum provided by the supplier of the electronic document. Note that the change of even a single character in a file typically leads to a radically different checksum.

## PORTABILITY¶

DOS 2.0 and up, with the MKS Toolkit. OS/2 with the MKS Toolkit. UNIX systems supporting the Korn shell or Bourne shell command interpreters, and POSIX.2 compliant cksum command.

 cksum (UNIX), sum (UNIX)