Crate posish

posish provides safe wrappers to libc functions. The current focus is on the functionality needed by cap-std and system-interface that isn’t provided by std or getrandom.

The wrappers perform the following tasks:

• Error values are translated to Results.
• Out-parameters are translated to return values.
• Path arguments can by any kind of string type.
• File descriptors are passed in through arguments implementing [AsFd] instead of as bare integers and returned as [OwnedFd]s.
• Constants use enums and bitflags types.
• Multiplexed functions (eg. fcntl, ioctl, etc.) are de-multiplexed.
• Variadic functions (eg. openat, etc.) are presented as non-variadic.
• Functions and types which need 64 suffixes to enable large-file support are used automatically.
• Behaviors that depend on the sizes of C types like long are hidden.
• File offsets and sizes are presented as i64 and u64 rather than off_t.
• In some places, more human-friendly and less historical-accident names are used.

Things they don’t do include:

• Emulating functions that aren’t natively supported on a platform.
• Detecting whether functions are supported at runtime.
• Hiding significant differences between platforms.
• Hiding ambient authorities.
• Imposing sandboxing features such as filesystem path or network address sandboxing.

See cap-std and system-interface for libraries which do hide ambient authorities and perform sandboxing.

Safety

This library uses the io-lifetimes crate to manage all OS resource handles, automatically ensuring I/O safety.

Modules

fs	Filesystem operations.
io	I/O operations.
net	Network-related operations.
path	Filesystem path operations.
process	Process-associated operations.
time	Time-related operations.