| Name | Type | Description |
| jappend | verb | append to jfile, (<i.2 3) jappend 'dat' |
| jcreate | verb | create jfile, jcreate 'dat' |
| jdup | verb | duplicate jfile, 'new' jdup 'dat' |
| jerase | verb | erase jfile, jerase 'dat' |
| jread | verb | read jfile, jread 'dat';2 |
| jreplace | verb | replace in jfile, ('new value';123) jreplace 'dat';2 5 |
| jsize | verb | return size of jfile, jsize 'dat' |