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Module (chicken errno)

This module provides access to the standard C errno value.

Be careful, if you're using threads, errno might be clobbered as soon as another thread calls a C function. To prevent this from happening, you can add (declare (disable-interrupts)) at the top of your file, or use the -disable-interrupts compiler option to avoid any context switches while a procedure in this file is running.

errno

errnoprocedure

Returns the error code of the last system call.

errno constants

errno/permconstant
errno/noentconstant
errno/srchconstant
errno/intrconstant
errno/ioconstant
errno/noexecconstant
errno/badfconstant
errno/childconstant
errno/nomemconstant
errno/accesconstant
errno/faultconstant
errno/busyconstant
errno/notdirconstant
errno/isdirconstant
errno/invalconstant
errno/mfileconstant
errno/nospcconstant
errno/spipeconstant
errno/pipeconstant
errno/againconstant
errno/rofsconstant
errno/existconstant
errno/wouldblockconstant

These variables contain error codes as returned by errno.

NOTE: On Windows, EWOULDBLOCK does not exist. For consistency, errno/wouldblock does exist, but it is defined as zero.

This does mean that in case there is no error, it looks like the errno/wouldblock error is returned. But you have to check the return code of a system call before accessing errno anyway, so this should typically never happen.


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