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GNU Info (python2.1-lib.info)File Descriptor OperationsFile Descriptor Operations -------------------------- These functions operate on I/O streams referred to using file descriptors. `close(fd)' Close file descriptor FD. Availability: Macintosh, UNIX, Windows. Note: this function is intended for low-level I/O and must be applied to a file descriptor as returned by `open()' or `pipe()'. To close a "file object" returned by the built-in function `open()' or by `popen()' or `fdopen()', use its `close()' method. `dup(fd)' Return a duplicate of file descriptor FD. Availability: Macintosh, UNIX, Windows. `dup2(fd, fd2)' Duplicate file descriptor FD to FD2, closing the latter first if necessary. Availability: UNIX, Windows. `fpathconf(fd, name)' Return system configuration information relevant to an open file. NAME specifies the configuration value to retrieve; it may be a string which is the name of a defined system value; these names are specified in a number of standards (POSIX.1, Unix95, Unix98, and others). Some platforms define additional names as well. The names known to the host operating system are given in the `pathconf_names' dictionary. For configuration variables not included in that mapping, passing an integer for NAME is also accepted. Availability: UNIX. If NAME is a string and is not known, `ValueError' is raised. If a specific value for NAME is not supported by the host system, even if it is included in `pathconf_names', an `OSError' is raised with `errno.EINVAL' for the error number. `fstat(fd)' Return status for file descriptor FD, like `stat()'. Availability: UNIX, Windows. `fstatvfs(fd)' Return information about the filesystem containing the file associated with file descriptor FD, like `statvfs()'. Availability: UNIX. `ftruncate(fd, length)' Truncate the file corresponding to file descriptor FD, so that it is at most LENGTH bytes in size. Availability: UNIX. `isatty(fd)' Return `1' if the file descriptor FD is open and connected to a tty(-like) device, else `0'. Availability: UNIX `lseek(fd, pos, how)' Set the current position of file descriptor FD to position POS, modified by HOW: `0' to set the position relative to the beginning of the file; `1' to set it relative to the current position; `2' to set it relative to the end of the file. Availability: Macintosh, UNIX, Windows. `open(file, flags[, mode])' Open the file FILE and set various flags according to FLAGS and possibly its mode according to MODE. The default MODE is `0777' (octal), and the current umask value is first masked out. Return the file descriptor for the newly opened file. Availability: Macintosh, UNIX, Windows. For a description of the flag and mode values, see the C run-time documentation; flag constants (like `O_RDONLY' and `O_WRONLY') are defined in this module too (see below). Note: this function is intended for low-level I/O. For normal usage, use the built-in function `open()', which returns a "file object" with `read()' and `write()' methods (and many more). `openpty()' Open a new pseudo-terminal pair. Return a pair of file descriptors `(MASTER, SLAVE)' for the pty and the tty, respectively. For a (slightly) more portable approach, use the `pty' module. Availability: Some flavors of UNIX `pipe()' Create a pipe. Return a pair of file descriptors `(R, W)' usable for reading and writing, respectively. Availability: UNIX, Windows. `read(fd, n)' Read at most N bytes from file descriptor FD. Return a string containing the bytes read. Availability: Macintosh, UNIX, Windows. Note: this function is intended for low-level I/O and must be applied to a file descriptor as returned by `open()' or `pipe()'. To read a "file object" returned by the built-in function `open()' or by `popen()' or `fdopen()', or `sys.stdin', use its `read()' or `readline()' methods. `tcgetpgrp(fd)' Return the process group associated with the terminal given by FD (an open file descriptor as returned by `open()'). Availability: UNIX. `tcsetpgrp(fd, pg)' Set the process group associated with the terminal given by FD (an open file descriptor as returned by `open()') to PG. Availability: UNIX. `ttyname(fd)' Return a string which specifies the terminal device associated with file-descriptor FD. If FD is not associated with a terminal device, an exception is raised. Availability: UNIX. `write(fd, str)' Write the string STR to file descriptor FD. Return the number of bytes actually written. Availability: Macintosh, UNIX, Windows. Note: this function is intended for low-level I/O and must be applied to a file descriptor as returned by `open()' or `pipe()'. To write a "file object" returned by the built-in function `open()' or by `popen()' or `fdopen()', or `sys.stdout' or `sys.stderr', use its `write()' method. The following data items are available for use in constructing the FLAGS parameter to the `open()' function. `O_RDONLY' `O_WRONLY' `O_RDWR' `O_NDELAY' `O_NONBLOCK' `O_APPEND' `O_DSYNC' `O_RSYNC' `O_SYNC' `O_NOCTTY' `O_CREAT' `O_EXCL' `O_TRUNC' Options for the FLAG argument to the `open()' function. These can be bit-wise OR'd together. Availability: Macintosh, UNIX, Windows. `O_BINARY' Option for the FLAG argument to the `open()' function. This can be bit-wise OR'd together with those listed above. Availability: Macintosh, Windows. automatically generated by info2www version 1.2.2.9 |