char *a; tanimi, hafiza'da sadece o pointer icin yer acar, onun isaret ettigi array'i malloc/calloc ile allocate etmeniz lazim. Sizin durumunuzda a'da NULL address var yani adres 0x0 ve siz o adrese birsey yazmaya calisiyorsunuz ve ama dogal olarak o adrese yazma yetkiniz yok.
On Mon, Mar 22, 2004 at 10:45:22PM +0200, "?zkan KIRIK" wrote: > Merhabalar, > > Bu sefer de cok ufak bir sorun icin sizleri rahatsiz ediyorum. freebsd ile > alakali degil ama... > > programda (char *) tipi bir degiskenin NULL olup olmadigini bi yerde kontrol etmem > gerekiyor. > ancak SEGMENTATION FAULT aliyorum. bunun nedenini incelemeye calistim. > GNU DEBUGGERda olmasa napariz acaba :)) > > ben ilgili kodlari yazayim: > > >>>>>>>>>>>>> > Line154: char *client_sid; /* acaba bir degeri olmayinca bellekte yer ayirmiyor mu > diye dusundum, degerini " "'a esitledim yine olmadi :) */ > ... > Line222: query_string = strtop(tmp_str, "$\n"); > Line223: client_sid = strtok(NULL, "$\n"); > Line224: if (*client_sid==NULL) > Line225: *client_sid='$'; > ... > >>>>>>>>>>>>> > > gdb ciktisinda bir nokta dikkatimi cekti : > >> (gdb) display *client_sid > >> 1: *client_sid = Error accessing memory address 0x0: Bad address. > nedeni neden olabilir ki acaba? > > > gdb ciktisi asagida: > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> > > kitap# gdb ipfwadmin 16848 > GNU gdb 5.2.1 (FreeBSD) > Copyright 2002 Free Software Foundation, Inc. > GDB is free software, covered by the GNU General Public License, and you are > welcome to change it and/or distribute copies of it under certain conditions. > Type "show copying" to see the conditions. > There is absolutely no warranty for GDB. Type "show warranty" for details. > This GDB was configured as "i386-undermydesk-freebsd"... > Attaching to program: /usr/home/ryland/ogren_c/new_ipfwadmin/ipfwadmin, process 16848 > Reading symbols from /usr/lib/libc.so.5...done. > Loaded symbols for /usr/lib/libc.so.5 > Reading symbols from /usr/libexec/ld-elf.so.1...done. > Loaded symbols for /usr/libexec/ld-elf.so.1 > 0x280ba4c3 in accept () from /usr/lib/libc.so.5 > (gdb) break 224 > Breakpoint 1 at 0x804961e: file ipfwadmin.c, line 224. > (gdb) continue > Continuing. > > Breakpoint 1, accept_request (client=5) at ipfwadmin.c:224 > 224 if (*client_sid==NULL) > (gdb) display *client_sid > 1: *client_sid = Error accessing memory address 0x0: Bad address. > Disabling display 1 to avoid infinite recursion. > (gdb) display client_sid > 2: client_sid = 0x0 > (gdb) display &client_sid > 3: &client_sid = (char **) 0xbfbfeacc > (gdb) step > > Program received signal SIGSEGV, Segmentation fault. > 0x08049624 in accept_request (client=5) at ipfwadmin.c:224 > 224 if (*client_sid==NULL) > 3: &client_sid = (char **) 0xbfbfeacc > 2: client_sid = 0x0 > (gdb) > > Program terminated with signal SIGSEGV, Segmentation fault. > The program no longer exists. > (gdb) q > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> > > > Su ufak tefek sorunlari atlatabilirsem program bu gece bitecek :) > > saygilar.tar.gz > Ozkan KIRIK > -- "When all else fails, read the instructions -- Murphy's Technology Laws" Murat Balaban http://www.enderunix.org --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Liste arsivi: http://lists.enderunix.org ve http://www.mail-archive.com/[EMAIL PROTECTED] http://ipucu.EnderUNIX.org - ihtiyac duyacaginiz kisa bilgiler bu sitede!
