This command is part of the posix extensions and needs to be imported to be available to the shell.
See Posix Commands
|-d,-directory||Creates a directory instead of a file|
|-s,-suffix suffix||optional suffix used for temporary file|
|-tempdir directory||Uses directory instead of $TMP|
|-p,-prefix prefix||optional prefix used for temporary file|
Creates a temporary file and outputs the full path name to stdout.
If -d is specified creates a directory instead of a file.
If -s is specified uses the supplied suffix otherwise no suffix is used.
If -p is specifies then prepends the supplied prefix otherwise "xmlsh" is used.
Note: an empty file is created not just a pathname. This is required to guarentee multiple calls to mktemp always return unique unused filenames.