File Descriptor Operations
These functions operate on I/O streams referred to with file descriptors:
-
close(fd) Closes file descriptor
fd. Availability: Macintosh, Unix, Windows.This function is intended for low-level I/O and must be applied to a file descriptor as returned by
open()orpipe(). To close a file object returned by the built-in functionopen(), bypopen(), orfdopen(), use itsclose()method.-
dup(fd) Returns a duplicate of file descriptor
fd. Availability: Macintosh, Unix, Windows.-
dup2(fd,fd2) Duplicates file descriptor
fdtofd2, closing the latter first if necessary. Availability: Unix, Windows.-
fstat(fd) Returns status for file descriptor
fd, likestat(). Availability: Unix, Windows.-
fstatvfs(fd) Returns information about the filesystem containing the file associated with file descriptor
fd, likestatvfs(). Availability: Unix.-
ftruncate(fd,length) Truncates the file corresponding to file descriptor
fd, so that it islengthbytes in size. Availability: Unix.-
lseek(fd,pos,how) Sets the current position of file descriptor
fdto positionpos, modified byhow: to set the position relative to the beginning of the file; 1 to set it relative to the current position; and 2 to set it relative to the end of the file. Availability: Macintosh, Unix, Windows.-
open(file,flags[,mode]) Opens the file
fileand sets various flags according toflagsand, possibly, its mode according tomode. The default mode is 0777 (octal), and the currentumaskvalue ...