Ft char *
Fn fgetln FILE *stream size_t *len
returns a pointer to the next line from the stream referenced by
Fa stream .
This line is
a C string as it does not end with a terminating
The length of the line, including the final newline,
is stored in the memory location to which
points and is guaranteed to be greater than 0 upon successful completion.
(Note, however, that if the line is the last
in a file that does not end in a newline,
the returned text will not contain a newline.)
Upon successful completion a pointer is returned;
this pointer becomes invalid after the next
(whether successful or not)
or as soon as the stream is closed.
does not distinguish between end-of-file and error; the routines
must be used
to determine which occurred.
If an error occurs, the global variable
is set to indicate the error.
The end-of-file condition is remembered, even on a terminal, and all
subsequent attempts to read will return
until the condition is
The text to which the returned pointer points may be modified,
provided that no changes are made beyond the returned size.
These changes are lost as soon as the pointer becomes invalid.
Bq Er EBADF
is not a stream open for reading.
may also fail and set
for any of the errors specified for the routines