2fe8fb192f
There is important information about booting non-ack images in docs/UPDATING. ack/aout-format images can't be built any more, and booting clang/ELF-format ones is a little different. Updating to the new boot monitor is recommended. Changes in this commit: . drop boot monitor -> allowing dropping ack support . facility to copy ELF boot files to /boot so that old boot monitor can still boot fairly easily, see UPDATING . no more ack-format libraries -> single-case libraries . some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases . drop several ack toolchain commands, but not all support commands (e.g. aal is gone but acksize is not yet). . a few libc files moved to netbsd libc dir . new /bin/date as minix date used code in libc/ . test compile fix . harmonize includes . /usr/lib is no longer special: without ack, /usr/lib plays no kind of special bootstrapping role any more and bootstrapping is done exclusively through packages, so releases depend even less on the state of the machine making them now. . rename nbsd_lib* to lib* . reduce mtree
155 lines
4.3 KiB
Groff
155 lines
4.3 KiB
Groff
.\" $NetBSD: fgetln.3,v 1.14 2004/05/10 17:15:28 drochner Exp $
|
|
.\"
|
|
.\" Copyright (c) 1990, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)fgetln.3 8.3 (Berkeley) 4/19/94
|
|
.\"
|
|
.Dd April 21, 2004
|
|
.Dt FGETLN 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm fgetln
|
|
.Nd get a line from a stream
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In stdio.h
|
|
.Ft char *
|
|
.Fn fgetln "FILE * restrict stream" "size_t * restrict len"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn fgetln
|
|
function
|
|
returns a pointer to the next line from the stream referenced by
|
|
.Fa stream .
|
|
This line is
|
|
.Em not
|
|
a C string as it does not end with a terminating
|
|
.Dv NUL
|
|
character.
|
|
The length of the line, including the final newline,
|
|
is stored in the memory location to which
|
|
.Fa len
|
|
points.
|
|
(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.)
|
|
.Sh RETURN VALUES
|
|
Upon successful completion a pointer is returned;
|
|
this pointer becomes invalid after the next
|
|
.Tn I/O
|
|
operation on
|
|
.Fa stream
|
|
(whether successful or not)
|
|
or as soon as the stream is closed.
|
|
Otherwise,
|
|
.Dv NULL
|
|
is returned.
|
|
The
|
|
.Fn fgetln
|
|
function
|
|
does not distinguish between end-of-file and error; the routines
|
|
.Xr feof 3
|
|
and
|
|
.Xr ferror 3
|
|
must be used
|
|
to determine which occurred.
|
|
If an error occurs, the global variable
|
|
.Va 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
|
|
.Dv NULL
|
|
until the condition is
|
|
cleared with
|
|
.Xr clearerr 3 .
|
|
.Pp
|
|
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.
|
|
.Sh ERRORS
|
|
.Bl -tag -width [EBADF]
|
|
.It Bq Er EBADF
|
|
The argument
|
|
.Fa stream
|
|
is not a stream open for reading.
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fn fgetln
|
|
function
|
|
may also fail and set
|
|
.Va errno
|
|
for any of the errors specified for the routines
|
|
.Xr fflush 3 ,
|
|
.Xr malloc 3 ,
|
|
.Xr read 2 ,
|
|
.Xr stat 2 ,
|
|
or
|
|
.Xr realloc 3 .
|
|
.Sh SEE ALSO
|
|
.Xr ferror 3 ,
|
|
.Xr fgets 3 ,
|
|
.Xr fopen 3 ,
|
|
.Xr putc 3
|
|
.Sh HISTORY
|
|
The
|
|
.Fn fgetln
|
|
function first appeared in
|
|
.Bx 4.4 .
|
|
.Sh CAVEATS
|
|
Since the returned buffer is not a C string (it is not null terminated), a
|
|
common practice is to replace the newline character with
|
|
.Sq \e0 .
|
|
However, if the last line in a file does not contain a newline,
|
|
the returned text won't contain a newline either.
|
|
The following code demonstrates how to deal with this problem by allocating a
|
|
temporary buffer:
|
|
.Bd -literal
|
|
char *buf, *lbuf;
|
|
size_t len;
|
|
|
|
lbuf = NULL;
|
|
while ((buf = fgetln(fp, &len))) {
|
|
if (buf[len - 1] == '\en')
|
|
buf[len - 1] = '\e0';
|
|
else {
|
|
if ((lbuf = (char *)malloc(len + 1)) == NULL)
|
|
err(1, NULL);
|
|
memcpy(lbuf, buf, len);
|
|
lbuf[len] = '\e0';
|
|
buf = lbuf;
|
|
}
|
|
printf("%s\en", buf);
|
|
|
|
if (lbuf != NULL) {
|
|
free(lbuf);
|
|
lbuf = NULL;
|
|
}
|
|
}
|
|
.Ed
|