Enum unshare::Error

pub enum Error {
    NixError,
    UnknownError,
    CreatePipe(i32),
    Fork(i32),
    Exec(i32),
    Chdir(i32),
    ParentDeathSignal(i32),
    PipeError(i32),
    WaitError(i32),
    StdioError(i32),
    SetUser(i32),
    ChangeRoot(i32),
    SetIdMap(i32),
    AuxCommandExited(i32),
    AuxCommandKilled(i32),
    SetPGid(i32),
    SetNs(i32),
    CapSet(i32),
    BeforeUnfreeze(Box<dyn Error + Send + Sync + 'static>),
    PreExec(i32),
}

Error runnning process

This type has very large number of options and it's enum only to be compact. Probably you shouldn't match on the error cases but just format it for user into string.

Variants

NixError

Unknown nix error

Frankly, this error should not happen when running process. We just keep it here in case nix returns this error, which should not happen.

UnknownError

Some invalid error code received from child application

CreatePipe(i32)

Error happened when we were trying to create pipe. The pipes used for two purposes: (a) for the process's stdio (Stdio::pipe() or Stdio::null()), (b) internally to wake up child process and return error back to the parent.

Fork(i32)

Error when forking/cloning process

Exec(i32)

Error when running execve() systemcall

Chdir(i32)

Error when setting working directory specified by user

ParentDeathSignal(i32)

Unable to set death signal (probably signal number invalid)

PipeError(i32)

Error reading/writing through one of the two signal pipes

WaitError(i32)

Error waiting for process (for some functions only, for example Command::status()). It probably means someone already waited for the process, for example it might be other thread, or signal handler.

StdioError(i32)

Error setting up stdio for process

SetUser(i32)

Could not set supplementary groups, group id or user id for the process

ChangeRoot(i32)

Error changing root, it explains chroot, pivot_root system calls and setting working directory inside new root. Also includes unmounting old file system for pivot_root case.

SetIdMap(i32)

Error setting uid or gid map. May be either problem running newuidmap/newgidmap command or writing the mapping file directly

AuxCommandExited(i32)

Auxillary command failed

There are two auxillary commands for now: newuidmap and newgidmap. They run only when uid mappings (user namespaces) are enabled.

Note that failing to run the binary results to SedIdMap(sys_errno), this error contains status code of command that was succesfullly spawned.

AuxCommandKilled(i32)

Auxillary command was killed by signal

Similar to AuxCommandExited but when command was killed

SetPGid(i32)

Error when calling setpgid function

SetNs(i32)

Error when calling setns syscall

CapSet(i32)

Error when calling capset syscall

BeforeUnfreeze(Box<dyn Error + Send + Sync + 'static>)

Before unfreeze callback error

PreExec(i32)

Before exec callback error

Implementations

impl Error

pub fn raw_os_error(&self) -> Option<i32>

Similarly to io::Error returns bare error code

Trait Implementations

impl Debug for Error

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Error

pub fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for Error

pub fn description(&self) -> &'static str

👎 Deprecated since 1.42.0:

use the Display impl or to_string()

pub fn source(&self) -> Option<&(dyn Error + 'static)>

The lower-level source of this error, if any.

pub fn backtrace(&self) -> Option<&Backtrace>

🔬 This is a nightly-only experimental API. (backtrace)

Returns a stack backtrace, if available, of where this error occurred.

pub fn cause(&self) -> Option<&dyn Error>

👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting