FUNCTIONS IN “LIST.H”

SINGLE CHARACTER FUNCTIONS

These functions act on a single character that represents a node in the List.

int Insert(char ch, int xcord, int ycord)

Inserts the character, ch, at the location in the linked list specified by the screen co-ordinates, xcord & ycord, passed as arguments. Characters to the right of the inserted character will be moved by one position to the right.

void Replace(char ch, int xcord, int ycord)

Replaces the character, ch, at the location in the linked list specified by the screen co-ordinates, xcord & ycord, passed as arguments.

NOTE: The above two functions are invoked depending upon the status of the INSERT key.

void Remove(int xcord, int ycord)

Deletes the character at the location in the linked list specified by the screen co-ordinates, xcord & ycord, passed as arguments.

NOTE: The above functions, on invocation, update the variable Chars in the HeadNode of the current List.

SINGLE LINE FUNCTIONS

These functions act on the group of Nodes constituting a line in the List.

int InsertLine(int xcord, int ycord)

This will insert a line at the specified location, xcord & ycord, and hence a new List in the data structure. It is to be noted that if this function is invoked with the cursor being at a non-terminal position will place the characters on the right of the cursor in the newly created List.

void RemoveLine(int ycord)

This will delete a complete line and hence a List in the data structure specifed by the ycord.

void AppendLine(int ycord)

This will append the line specified by the ycord, to the line preceding it in the List.

NOTE: The above functions, on invocation, update the variable Lines.

FILE HANDLING FUNCTIONS

These functions perform the specified I/O operations on the file.

int SaveFile(char *filename)

This function will write the contents of the List on the file specified by the filename. If a file with the filename already exists, then it is overwritten.

int LoadFile(char *filename)

This function will the load the contents of the file specified by the filename into the List.

void DeleteList(void)

This function acts as an explicit destructor for the List. Whenever a new file is to be opened, the present file contents stored in the List are flushed and Head is made to point to NULL. Also, Chars & Lines are updated.

SCREEN MANIPULATION FUNCTION

This function will update the screen contents.

void DispLine(int ycord, char *str)

This function will return the line contents at the specified ycord, in str to the calling function.

STATUS INDICATING FUNCTIONS

These functions will return values indicating the status of the List.

int ReturnChars(int ycord)

This function will return the number of characters present in the line specified by ycord.

int ReturnLines(void)

This function will return the number of lines present in the List.

int ReturnWords(int ycord)

This function will return the number of words in the line specified by ycord.

SEARCH FUNCTIONS

These functions are used to perform search operations.

int FindWord(char *str , int *xcord , int *ycord)

This function searches for a particular string specified by str, and if found, moves the screen cursor to the end of the matched string.

int FindReplaceWord(char *str , char *repstr, int *xcord, int *ycord)

This function searches for a particular string specified by str, and if found, replaces this str with the replace string, repstr.

EDIT FUNCTIONS

These functions are used to perform basic editing operations.

void Cut(List *Temp, int x1, int y1, int x2, int y2)

This function cuts the List from the co-ordinates (x1, y1) to (x2, y2) and places it in a temporary list, Temp. The character after (x2, y2) is appended to the character preceding (x1, y1).

int Copy(List *Temp, int x1 , int y1, int x2, int y2)

This function copies the List from the co-ordinates (x1, y1) to (x2, y2) and places it in a temporary list, Temp.

int Paste(List *Temp, int x1 , int y1, int x2, int y2)

This function inserts into the List, the characters from the co-ordinates (x1, y1) to (x2, y2) from the temporary list, Temp.

NOTE: These functions preserve the format of the file. For e.g. if the copied portion of the file extends over multiple lines, then during the paste operation the inserted portion will contain line breaks at the same positions as in the copied portion.

top

ZAP works