cheetsheet

##	USEFUL FUNCTIONS



open		# Opens the file in memory 
read		# reads the file fd into buffer
write		# writes buffer to the file denoted by fd
close		# closes the file denoted by fd
stat		# To extract properties of any file in variable of type 'struct stat'
fstat		# same as stat (uses fd instead of pathname)
lstat		# same as stat but if the filetype is a 'symlink', then it obtains the info about the
		# link itself rather than derefering to the link and returning info. about the file
		# that the 'symbolic link' points to.

writev		# 'vector write' enables you to write multiple discontiguous regions of memory to a fd
		# in a single write. 

fileno		# To get the fd of a file opened by fopen() (i.e. from C standard lib -> low-level I/O)
fdopen		# To get a file stream *pointer from fd (i.e. from low-level I/O -> C standard lib)

getcwd		# obtains current working directory
chdir		# changes current working directory to path provided as argument
mkdir 		# creates a new directory
rmdir		# Deletes a directory.
unlink		# it unlinks the file (or directory) from the directory containing it.
rename 		# rename/moves a file.

opendir		# Opens a directory into memory (for you to examine). Returns a 'DIR *' handle.
readdir		# passing the DIR * handle and calling repeatedly, returns pointer to 'struct dirent'.
			# returns NULL when you reach end of directory's content.
closedir	# passing DIR * handle to end the directory listing operation.


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assert
time
localtime
asctime