RAMFILE(4)RAMFILE(4)NAME
ramfile - synthesise file
SYNOPSIS
ramfile file [ data ]
DESCRIPTION
Ramfile puts a virtual file in the name space at file, and services
file requests on it. Data written to the file is stored in ramfile's
memory; read requests return the previously stored data. If the
optional data argument is provided, the file will initially contain
that text. The parent directory of file must exist; ramfile creates a
union mount on that directory, and if file previously existed, the syn‐
thesised file will hide it.
Ramfile uses sys-file2chan(2), which simplifies implementation but pre‐
vents it from knowing when the file has been truncated. Instead, it
truncates the file on any write to the start of the file (offset 0),
allowing cp(1) to copy in new contents, and text editors to edit it.
Indeed, the file will be usable by all applications that do not rely on
updating parts of the file in place, or if they do, do not update the
start of the file.
SOURCE
/appl/cmd/ramfile.b
SEE ALSObind(1), sys-file2chan(2), srv(3), memfs(4)BUGS
Ramfile cannot tell when the path has been unmounted; the only option
is to kill(1) it.
The file always appears to have zero length to sys-stat(2), which pre‐
vents loading a Dis file from it.
RAMFILE(4)