Python Pocket Reference, 3rd Edition

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Python Pocket Reference

errno and the corresponding string, as would be printed

by the C function

perror(). See the module errno in the

Python Library Reference for names of the error codes

defined by the underlying OS.

When exceptions are classes, this exception carries two

attributes:

errno, the value of the C errno variable; and

strerror, the corresponding error message from

strerror(). For exceptions that involve a file pathname

(e.g.,

chdir(), unlink()), the exception instance also

contains the attribute

filename, the filename passed in.

name

Name of OS-specific modules whose names are copied to

the top level of

os (e.g., posix, nt, dos, mac, os2, ce,or

java). See also platform in the section “The sys Mod-

ule,” earlier in this book.

path

Nested module for portable pathname-based utilities.

For example,

os.path.split is a platform-independent

directory name tool that internally uses an appropriate

platform-specific call.

Portability Constants

This section describes tools for parsing and building direc-

tory and search path strings portably. They are automati-

cally set to the appropriate value for the platform on which a

script is running.

curdir

String used to represent current directory (e.g., . for

POSIX,

: for Macintosh).

pardir

String used to represent parent directory (e.g., .. for

POSIX,

:: for Macintosh).

sep

String used to separate directories (e.g., / for Unix, \ for

Windows, or

: for Macintosh).