hdel
Delete a file or folder
hdel x hdel[x]
Where x is a file symbol atom, deletes the file or folder and returns x.
q)hdel`:test.txt / delete test.txt in current working directory
`:test.txt
q)hdel`:test.txt / should generate an error
'test.txt: No such file or directory
hdel can delete folders only if empty.
To delete a folder and its contents, recursively
/diR gets recursive dir listing
q)diR:{$[11h=type d:key x;raze x,.z.s each` sv/:x,/:d;d]}
/hide power behind nuke
q)nuke:hdel each desc diR@ / desc sort!
q)nuke`:mydir
For a general visitor pattern with hdel
q)visitNode:{if[11h=type d:key y;.z.s[x]each` sv/:y,/:d;];x y}
q)nuke:visitNode[hdel]
Unlike Linux, Windows doesn’t allow one to overwrite files which are memory mapped, and it takes some mS after unmapping for that to become possible.