Reading and writing to files in DROPS

Rene Wittmann Rene.B.Wittmann at
Wed May 18 18:00:49 CEST 2005


I'm still trying to write to a file in DROPS. What is the best way to do

When trying to use the OSKIT support (at least I think that I use it...)
it doesn't work, maybe I'm thinking too straightforward, but my code
looks simply this way:

#include <stdio.h>

char LOG_tag[9]="tso_test";

int main(int argc, const char**argv){
	FILE *handle;
	int i;
	handle = fopen("/tmp/check","w+");
	printf("before fileprinting\n");
	fprintf(handle,"Just a writing to file test.");
	printf("after fileprinting\n");
	printf("after closing\n");
	return 0;

My Makefile (compiling without error or warning):
PKGDIR  ?= ../..
L4DIR   ?= $(PKGDIR)/../..
TARGET  = tso_test

DEFAULT_RELOC   = 0x02000000
MODE    = l4env
SRC_C   = tso_test.c
LOGTAG  = $(addprefix ",$(addsuffix ",$(TARGET)))

include $(L4DIR)/mk/   

Finally my config:
title vmware tso_test
root (hd0,1)
kernel /drops/drops/bin/x86_586/l4v2/rmgr -sigma0
module /drops/l4/kernel/fiasco/build/main -nokdb -nowait -serial -serial_esc
module /drops/drops/bin/x86_586/l4v2/sigma0
modaddr 0x02000000
module /drops/drops/bin/x86_586/l4v2/names
module /drops/drops/bin/x86_586/l4v2/log
module /drops/drops/bin/x86_586/l4v2/dm_phys
module /drops/drops/bin/x86_586/l4v2/simple_ts
module /drops/drops/bin/x86_586/l4v2/tso_test

But the error message:
names   | Fiasco detected, registering thread names at kernel
tso_test| OSKit support: using 4096KB at 0x00180000 as heap
tso_test| fs_init: WARNING: No Filesystem
tso_test| before fileprinting
tso_test| Just a writing to file test.after fileprinting
tso_test| L4RM: [PF] read at 0x000000c, eip 0200e54b, src 9.02
tso_test| [9.0] l4rm/lib/src/pagefault.c:78:__unknown_pf():
tso_test|  unhandled page fault
(9.00) jdb:

Of course, I can see that fs_init says about "No Filesystem". Is it
because I'm using reiserfs? Would it work with ext2?

Or is there a better way writing to a file in DROPS? Maybe some
L4-specific functions?

Regards, Rene

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