NAME
fgetln — get a line from a streamLIBRARY
library “libbsd”SYNOPSIS
#include <stdio.h> (See libbsd(7) for include usage.)char *
fgetln(FILE *stream, size_t *len);
DESCRIPTION
The fgetln() function returns a pointer to the next line from the stream referenced by stream. This line is not a C string as it does not end with a terminatingNUL
character. The
length of the line, including the final newline, is stored in the memory
location to which len 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.)
RETURN VALUES
Upon successful completion a pointer is returned; this pointer becomes invalid after the next I/O operation on stream (whether successful or not) or as soon as the stream is closed. Otherwise,NULL
is returned. The
fgetln() function does not distinguish between
end-of-file and error; the routines feof(3) and
ferror(3) must be used to determine which
occurred. If an error occurs, the global variable
errno 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 NULL
until the
condition is cleared with clearerr(3).
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.
ERRORS
- [
EBADF
] - The argument stream is not a stream open for reading.
SEE ALSO
ferror(3), fgets(3), fgetwln(3bsd), fopen(3), putc(3)HISTORY
The fgetln() function first appeared in 4.4BSD.April 19, 1994 | Debian |