logger To keep track every file access and modifications this library use the log_entry structure The log_entry structure contains the following fields :	1. uid : user id (positive integer)	2. access_type : access type values [0-2]	3. action_denied : is action denied values [0-1]	4. time_t timestamp : date and time that the action occurred	5. file : filename (string)	6. fingerprint : file fingerprint 

write_log_file This function is responsible to write the log_entry to file_logging file Because the size of each log_entry is dynamic , the function writes two slashes between the field file and the field fingerprint so that it can read the log_entry The log entries recorded as hex values 

fopen This function keep track every file access This function distinguish the creation ​of a file from the ​opening ​of an existing file using the function access before the original fopen is called The fingerprint of the file is setting to null either the file does not exist or user has not got read access to file @return : return the original fopen file pointer 

fwrite This function keep track every file modification This function take the name of the file using the realink function with appropriately arguments The computation of the fingerprint is done after calling the original fwrite The function get the results that have been written using the function fflush and after compute the fingerprint The fingerprint of the file is setting to null when user has not got read access to file @return : return the original fwrite size_t 

acmonitor To implemented the list_unauthorized_accesses and list_file_modifications functions, was used the log_entry structure. The log_entry structure contains the following fields :	1. uid : user id (positive integer)	2. access_type : access type values [0-2]	3. action_denied : is action denied values [0-1]	4. time_t timestamp : date and time that the action occurred	5. file : filename (string)	6. fingerprint : file fingerprint	7. access_multiple_files : contains the number of different accessed files without permission from each user (used on list_unauthorized_accesses)	8. accessed_user_files : hyphen separated list of different accessed filenames without permission of user (used on list_unauthorized_accesses)	9. file_contents_modified : contains the number of times that the file was indeed modified of each user (used on list_file_modifications) 

list_unauthorized_accesses This function returns all users that tried to access more than 7 different files without having permissions. 

list_file_modifications This function print a table with the number of times each user has modified the file. This function use the last_modified_fingerprint string that contains the last modified fingerprint of file Used to comparing with fingerprint of the current log_entry so the log_entry which was read at that time and is updated by reading the_logging file when necessary 

test_aclog To demonstrated the above tasks list_unauthorized_accesses and list_file_modifications on this function implemented the following : 1. Created a malicious user who has access to 8 different files without has got permission (list_unauthorized_accesses) 2. A user who indeed modified the contents of the file user1 two times ( ./acmonitor -i user1 ) 

Options: -m Prints malicious users -i <filename> Prints table of users that modified the file given and the number of modifications -h Help message