String operation gstring in GTK

Gstring
In addition to using gchar * for string processing, g l I B also defines a new data type: g s t r I n g. It is similar to the string type of standard C, but g s t r I n gcan automatically increase. Its string data ends with n u L. These features can prevent Program Buffer overflow. This is a very important feature. The following is the definition of g s t r I n g:
Struct gstring
{
Gchar * STR;/* points to the st' RSI ncgurrent/0-terminated value .*/
Gint Len;/* Current length */
};
Use the following function to create a new g s t r I n g variable:
Gstring * g_string_new (gchar * init );
This function creates a g s t r I n g, copies the string value I n I t to g s t r I n g, and returns a pointer to it. If the I n I t parameter is n u L, create an empty g s t r I n g.
Void g_string_free (gstring * string, Gint free_segment );
This function releases the memory occupied by s t r I n g. The f r e _ s e g m e n t parameter is a Boolean variable. If the f r e _ s e g m e n t parameter is t r u e, it also releases the character data.
Gstring * g_string_assign (gstring * lval, const gchar * rval );
This function copies characters from R v a l to l v a l and destroys the original content of l v a l. Note that if necessary, l v a l will be extended to hold the content of the string. This is the same as the standard string replication function s t r c p y. The meanings of the following functions are obvious. The function ending with _ c accepts a character rather than a string.
Take the s t r I N G string and generate a substring with the length of l e n:
Gstring * g_string_truncate (gstring * string, Gint Len );
Append the string v a l to s t r I n g and return a new string:
Gstring * g_string_append (gstring * string, gchar * val );
Append character C to s t r I n g and return a new string:
Gstring * g_string_append_c (gstring * string, gchar C );
Insert the string v a l before s t r I n g to generate a new string:
Gstring * g_string_prepend (gstring * string, gchar * val );
Insert character C to s t r I n g to generate a new string:
Gstring * g_string_prepend_c (gstring * string, gchar C );
Write a formatted string to s t r I n g, similar to the standard s p r I n t f function:
Void g_string_sprintf (gstring * string, gchar * FMT ,...);
Append a formatted string to the end of s t r I n g, which is slightly different from the previous function:
Void g_string_sprintfa (gstring * string, gchar * FMT ,...);