file-write-access?

[procedure] file-read-access? filename [realuid?]

[procedure] file-write-access? filename [realuid?]

[procedure] file-execute-access? filename [realuid?]

Chicken: check file accessibility. Use effective uid unless realuid? is given and true. See Concept:FileSystem, file-permissions.

Some implementations have file-is-readable? or file-readable? etc.

Gauche has sys-access which is POSIX access() interface.