Search Results

Search found 29194 results on 1168 pages for 'non null'.

Page 21/1168 | < Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >

  • Non-Blocking I/O Made Possible in Java

    Java SE7 "Dolphin" release is nearing and we're chomping at the bit. So let's dig in and review non-blocking IO, a feature of java.nio (New I/O) package that is a part of Java v1.4, v1.5 and v1.6 and we'll also take a peek at the java.nio.file (NIO.2) package.

    Read the article

  • Is it possible to run dhcpd3 as non-root user in a chroot jail?

    - by Lenain
    Hi everyone. I would like to run dhcpd3 from a chroot jail on Debian Lenny. At the moment, I can run it as root from my jail. Now I want to do this as non-root user (as "-u blah -t /path/to/jail" Bind option). If I start my process like this : start-stop-daemon --chroot /home/jails/dhcp --chuid dhcp \ --start --pidfile /home/jails/dhcp/var/run/dhcp.pid --exec /usr/sbin/dhcpd3 I get stuck with these errors : Internet Systems Consortium DHCP Server V3.1.1 Copyright 2004-2008 Internet Systems Consortium. All rights reserved. For info, please visit http://www.isc.org/sw/dhcp/ unable to create icmp socket: Operation not permitted Wrote 0 deleted host decls to leases file. Wrote 0 new dynamic host decls to leases file. Wrote 0 leases to leases file. Open a socket for LPF: Operation not permitted strace : brk(0) = 0x911b000 fcntl64(0, F_GETFD) = 0 fcntl64(1, F_GETFD) = 0 fcntl64(2, F_GETFD) = 0 access("/etc/suid-debug", F_OK) = -1 ENOENT (No such file or directory) access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb775d000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) open("/etc/ld.so.cache", O_RDONLY) = -1 ENOENT (No such file or directory) open("/lib/tls/i686/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/i686/cmov", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/tls/i686/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/i686", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/tls/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/cmov", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/tls/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/i686/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i686/cmov", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/i686/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i686", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/cmov", 0xbfc2ac84) = -1 ENOENT (No such file or directory) open("/lib/libc.so.6", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\260e\1\0004\0\0\0t"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=1294572, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb775c000 mmap2(NULL, 1300080, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb761e000 mmap2(0xb7756000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x138) = 0xb7756000 mmap2(0xb7759000, 9840, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7759000 close(3) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb761d000 set_thread_area({entry_number:-1 - 6, base_addr:0xb761d6b0, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}) = 0 mprotect(0xb7756000, 4096, PROT_READ) = 0 open("/dev/null", O_RDWR) = 3 close(3) = 0 brk(0) = 0x911b000 brk(0x913c000) = 0x913c000 socket(PF_FILE, SOCK_DGRAM, 0) = 3 fcntl64(3, F_SETFD, FD_CLOEXEC) = 0 connect(3, {sa_family=AF_FILE, path="/dev/log"...}, 110) = 0 time(NULL) = 1284760816 open("/etc/localtime", O_RDONLY) = 4 fstat64(4, {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 fstat64(4, {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb761c000 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0\f\0\0\0\0\0"..., 4096) = 2945 _llseek(4, -28, [2917], SEEK_CUR) = 0 read(4, "\nCET-1CEST,M3.5.0,M10.5.0/3\n"..., 4096) = 28 close(4) = 0 munmap(0xb761c000, 4096) = 0 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Intern"..., 73, MSG_NOSIGNAL) = 73 write(2, "Internet Systems Consortium DHCP "..., 46Internet Systems Consortium DHCP Server V3.1.1) = 46 write(2, "\n"..., 1 ) = 1 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Copyri"..., 75, MSG_NOSIGNAL) = 75 write(2, "Copyright 2004-2008 Internet Syst"..., 48Copyright 2004-2008 Internet Systems Consortium.) = 48 write(2, "\n"..., 1 ) = 1 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: All ri"..., 47, MSG_NOSIGNAL) = 47 write(2, "All rights reserved."..., 20All rights reserved.) = 20 write(2, "\n"..., 1 ) = 1 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: For in"..., 77, MSG_NOSIGNAL) = 77 write(2, "For info, please visit http://www"..., 50For info, please visit http://www.isc.org/sw/dhcp/) = 50 write(2, "\n"..., 1 ) = 1 socket(PF_FILE, SOCK_STREAM, 0) = 4 fcntl64(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0 connect(4, {sa_family=AF_FILE, path="/var/run/nscd/socket"...}, 110) = -1 ENOENT (No such file or directory) close(4) = 0 socket(PF_FILE, SOCK_STREAM, 0) = 4 fcntl64(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0 connect(4, {sa_family=AF_FILE, path="/var/run/nscd/socket"...}, 110) = -1 ENOENT (No such file or directory) close(4) = 0 open("/etc/nsswitch.conf", O_RDONLY) = 4 fstat64(4, {st_mode=S_IFREG|0644, st_size=475, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb761c000 read(4, "# /etc/nsswitch.conf\n#\n# Example "..., 4096) = 475 read(4, ""..., 4096) = 0 close(4) = 0 munmap(0xb761c000, 4096) = 0 open("/lib/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/i686/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/i686/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/i686/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/i686", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i686/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i686/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i686/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i686", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/tls/i686/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/tls/i686/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/tls/i686/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/tls/i686", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/tls/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/tls/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/tls/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/tls", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/i686/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/i686/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/i686/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/i686", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/i486-linux-gnu/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/i486-linux-gnu", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/tls/i686/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/tls/i686/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/tls/i686/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/tls/i686", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/tls/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/tls/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/tls/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/tls", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/i686/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/i686/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/i686/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/i686", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/cmov/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu/cmov", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/usr/lib/i486-linux-gnu/libnss_db.so.2", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/i486-linux-gnu", 0xbfc2ad5c) = -1 ENOENT (No such file or directory) open("/lib/libnss_files.so.2", O_RDONLY) = 4 read(4, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\320\30\0\0004\0\0\0\250"..., 512) = 512 fstat64(4, {st_mode=S_IFREG|0644, st_size=38408, ...}) = 0 mmap2(NULL, 41624, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 4, 0) = 0xb7612000 mmap2(0xb761b000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 4, 0x8) = 0xb761b000 close(4) = 0 open("/etc/services", O_RDONLY|O_CLOEXEC) = 4 fcntl64(4, F_GETFD) = 0x1 (flags FD_CLOEXEC) fstat64(4, {st_mode=S_IFREG|0644, st_size=18480, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7611000 read(4, "# Network services, Internet styl"..., 4096) = 4096 read(4, "9/tcp\t\t\t\t# Quick Mail Transfer Pr"..., 4096) = 4096 read(4, "note\t1352/tcp\tlotusnotes\t# Lotus "..., 4096) = 4096 read(4, "tion\nafs3-kaserver\t7004/udp\nafs3-"..., 4096) = 4096 read(4, "backup\t2989/tcp\t\t\t# Afmbackup sys"..., 4096) = 2096 read(4, ""..., 4096) = 0 close(4) = 0 munmap(0xb7611000, 4096) = 0 time(NULL) = 1284760816 open("/etc/protocols", O_RDONLY|O_CLOEXEC) = 4 fstat64(4, {st_mode=S_IFREG|0644, st_size=2626, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7611000 read(4, "# Internet (IP) protocols\n#\n# Upd"..., 4096) = 2626 close(4) = 0 munmap(0xb7611000, 4096) = 0 socket(PF_INET, SOCK_RAW, IPPROTO_ICMP) = -1 EPERM (Operation not permitted) time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: unable"..., 80, MSG_NOSIGNAL) = 80 write(2, "unable to create icmp socket: Ope"..., 53unable to create icmp socket: Operation not permitted) = 53 write(2, "\n"..., 1 ) = 1 open("/etc/dhcp3/dhcpd.conf", O_RDONLY) = 4 lseek(4, 0, SEEK_END) = 1426 lseek(4, 0, SEEK_SET) = 0 read(4, "#----------------------------\n# G"..., 1426) = 1426 close(4) = 0 mmap2(NULL, 401408, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb75b0000 mmap2(NULL, 401408, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb754e000 mmap2(NULL, 401408, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb74ec000 brk(0x916f000) = 0x916f000 close(3) = 0 socket(PF_FILE, SOCK_DGRAM, 0) = 3 fcntl64(3, F_SETFD, FD_CLOEXEC) = 0 connect(3, {sa_family=AF_FILE, path="/dev/log"...}, 110) = 0 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Inter"..., 74, MSG_NOSIGNAL) = 74 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Copyr"..., 76, MSG_NOSIGNAL) = 76 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: All r"..., 48, MSG_NOSIGNAL) = 48 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: For i"..., 78, MSG_NOSIGNAL) = 78 open("/var/lib/dhcp3/dhcpd.leases", O_RDONLY) = 4 lseek(4, 0, SEEK_END) = 126 lseek(4, 0, SEEK_SET) = 0 read(4, "# The format of this file is docu"..., 126) = 126 close(4) = 0 open("/var/lib/dhcp3/dhcpd.leases", O_WRONLY|O_CREAT|O_APPEND, 0666) = 4 fstat64(4, {st_mode=S_IFREG|0644, st_size=126, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb74eb000 fstat64(4, {st_mode=S_IFREG|0644, st_size=126, ...}) = 0 _llseek(4, 126, [126], SEEK_SET) = 0 time(NULL) = 1284760816 time(NULL) = 1284760816 open("/var/lib/dhcp3/dhcpd.leases.1284760816", O_WRONLY|O_CREAT|O_TRUNC, 0664) = 5 fcntl64(5, F_GETFL) = 0x1 (flags O_WRONLY) fstat64(5, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb74ea000 _llseek(5, 0, [0], SEEK_CUR) = 0 close(4) = 0 munmap(0xb74eb000, 4096) = 0 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Wrote"..., 70, MSG_NOSIGNAL) = 70 write(2, "Wrote 0 deleted host decls to lea"..., 42Wrote 0 deleted host decls to leases file.) = 42 write(2, "\n"..., 1 ) = 1 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Wrote"..., 74, MSG_NOSIGNAL) = 74 write(2, "Wrote 0 new dynamic host decls to"..., 46Wrote 0 new dynamic host decls to leases file.) = 46 write(2, "\n"..., 1 ) = 1 time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Wrote"..., 58, MSG_NOSIGNAL) = 58 write(2, "Wrote 0 leases to leases file."..., 30Wrote 0 leases to leases file.) = 30 write(2, "\n"..., 1 ) = 1 write(5, "# The format of this file is docu"..., 126) = 126 fsync(5) = 0 unlink("/var/lib/dhcp3/dhcpd.leases~") = 0 link("/var/lib/dhcp3/dhcpd.leases", "/var/lib/dhcp3/dhcpd.leases~") = 0 rename("/var/lib/dhcp3/dhcpd.leases.1284760816", "/var/lib/dhcp3/dhcpd.leases") = 0 socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP) = 4 ioctl(4, SIOCGIFCONF, {0 - 64, NULL}) = 0 ioctl(4, SIOCGIFCONF, {64, {{"lo", {AF_INET, inet_addr("127.0.0.1")}}, {"eth0", {AF_INET, inet_addr("192.168.0.10")}}}}) = 0 ioctl(4, SIOCGIFFLAGS, {ifr_name="lo", ifr_flags=IFF_UP|IFF_LOOPBACK|IFF_RUNNING}) = 0 ioctl(4, SIOCGIFFLAGS, {ifr_name="eth0", ifr_flags=IFF_UP|IFF_BROADCAST|IFF_RUNNING|IFF_MULTICAST}) = 0 ioctl(4, SIOCGIFHWADDR, {ifr_name="eth0", ifr_hwaddr=00:c0:26:87:55:c0}) = 0 socket(PF_PACKET, SOCK_PACKET, 768) = -1 EPERM (Operation not permitted) time(NULL) = 1284760816 stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 send(3, "Sep 18 00:00:16 dhcpd: Open "..., 74, MSG_NOSIGNAL) = 74 write(2, "Open a socket for LPF: Operation "..., 46Open a socket for LPF: Operation not permitted) = 46 write(2, "\n"..., 1 ) = 1 exit_group(1) = ? I understand that dhcpd wants to create sockets on port 67... but I don't know how to authorize that through the chroot. Any idea?

    Read the article

  • Solving Null Entity Problems with JPA Data Controls in PS1

    - by shay.shmeltzer
    Turns out there is a slight bug that seems to prevent you from doing interactions (update, scroll) with the results of a JPA named query that you dropped on a page using ADF Binding. People are running into this when they are doing the EJB tutorial on OTN for example. The problem is that the way the binding is set up for you automatically doesn't allow you to actually access the iterator set of records to do follow up operations. When I last checked this was solved in the next release of JDeveloper, but in the meantime there is a quick simple way to resolve the issue by changing the refresh condition of the oiterator in your page binding. Here is a little demo that shows the problem and the solution:

    Read the article

  • Non-English Character Display in Oracle SQL Developer

    - by thatjeffsmith
    I get a variation on this question at least once a week, if not more frequently. I’m from Israel, and the language on the databases is Hebrew. When I use the old and deprecated SQL*Plus (windows rich client) I can see the hebrew clearly, when I use the latest SQL Developer, I get gibberish. This question appears on the forums about every week or so as well. So what’s the deal? Well, it starts with a basic misunderstanding of NLS Client parameters. These should accurately reflect the language and locality setup on your LOCAL machine. DO NOT COPY what’s set in the database. The these parameters work together with the database so that information can be transferred back and forth correctly. Having the wrong NLS parameters locally can be bad. [ORACLE DOCS]Setting the NLS_LANG parameter properly is essential to proper data conversion. The character set that is specified by the NLS_LANG parameter should reflect the setting for the client operating system. Setting NLS_LANG correctly enables proper conversion from the client operating system character encoding to the database character set. When these settings are the same, Oracle Database assumes that the data being sent or received is encoded in the same character set as the database character set, so character set validation or conversion may not be performed. This can lead to corrupt data if conversions are necessary. OK, so what are you supposed to do? Set the Font! 9 times out of 10, this preference fixes the problem with display issues. Make sure you set a Font that supports the characters you’re trying to display. It’s as simple as that. This preference defines the font used to display characters in the editors and the data grids. If you have it set to a font that doesn’t have Hebrew character support – you’re not going to see Hebrew in SQL Developer. A few years ago…wow, like 15 years ago, I learned that the Tohama Font is pretty Unicode-friendly. Bad Font Selection A Font that’s not non-English friendly Good Font Selection Exact same text, except rendered with the Tahoma font Summary Having problems seeing non-English text in SQL Developer? Check the font! And do not start messing with NLS parameters without talking to your DBA first.

    Read the article

  • C#/.NET Little Wonders: The Nullable static class

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Today we’re going to look at an interesting Little Wonder that can be used to mitigate what could be considered a Little Pitfall.  The Little Wonder we’ll be examining is the System.Nullable static class.  No, not the System.Nullable<T> class, but a static helper class that has one useful method in particular that we will examine… but first, let’s look at the Little Pitfall that makes this wonder so useful. Little Pitfall: Comparing nullable value types using <, >, <=, >= Examine this piece of code, without examining it too deeply, what’s your gut reaction as to the result? 1: int? x = null; 2:  3: if (x < 100) 4: { 5: Console.WriteLine("True, {0} is less than 100.", 6: x.HasValue ? x.ToString() : "null"); 7: } 8: else 9: { 10: Console.WriteLine("False, {0} is NOT less than 100.", 11: x.HasValue ? x.ToString() : "null"); 12: } Your gut would be to say true right?  It would seem to make sense that a null integer is less than the integer constant 100.  But the result is actually false!  The null value is not less than 100 according to the less-than operator. It looks even more outrageous when you consider this also evaluates to false: 1: int? x = null; 2:  3: if (x < int.MaxValue) 4: { 5: // ... 6: } So, are we saying that null is less than every valid int value?  If that were true, null should be less than int.MinValue, right?  Well… no: 1: int? x = null; 2:  3: // um... hold on here, x is NOT less than min value? 4: if (x < int.MinValue) 5: { 6: // ... 7: } So what’s going on here?  If we use greater than instead of less than, we see the same little dilemma: 1: int? x = null; 2:  3: // once again, null is not greater than anything either... 4: if (x > int.MinValue) 5: { 6: // ... 7: } It turns out that four of the comparison operators (<, <=, >, >=) are designed to return false anytime at least one of the arguments is null when comparing System.Nullable wrapped types that expose the comparison operators (short, int, float, double, DateTime, TimeSpan, etc.).  What’s even odder is that even though the two equality operators (== and !=) work correctly, >= and <= have the same issue as < and > and return false if both System.Nullable wrapped operator comparable types are null! 1: DateTime? x = null; 2: DateTime? y = null; 3:  4: if (x <= y) 5: { 6: Console.WriteLine("You'd think this is true, since both are null, but it's not."); 7: } 8: else 9: { 10: Console.WriteLine("It's false because <=, <, >, >= don't work on null."); 11: } To make matters even more confusing, take for example your usual check to see if something is less than, greater to, or equal: 1: int? x = null; 2: int? y = 100; 3:  4: if (x < y) 5: { 6: Console.WriteLine("X is less than Y"); 7: } 8: else if (x > y) 9: { 10: Console.WriteLine("X is greater than Y"); 11: } 12: else 13: { 14: // We fall into the "equals" assumption, but clearly null != 100! 15: Console.WriteLine("X is equal to Y"); 16: } Yes, this code outputs “X is equal to Y” because both the less-than and greater-than operators return false when a Nullable wrapped operator comparable type is null.  This violates a lot of our assumptions because we assume is something is not less than something, and it’s not greater than something, it must be equal.  So keep in mind, that the only two comparison operators that work on Nullable wrapped types where at least one is null are the equals (==) and not equals (!=) operators: 1: int? x = null; 2: int? y = 100; 3:  4: if (x == y) 5: { 6: Console.WriteLine("False, x is null, y is not."); 7: } 8:  9: if (x != y) 10: { 11: Console.WriteLine("True, x is null, y is not."); 12: } Solution: The Nullable static class So we’ve seen that <, <=, >, and >= have some interesting and perhaps unexpected behaviors that can trip up a novice developer who isn’t expecting the kinks that System.Nullable<T> types with comparison operators can throw.  How can we easily mitigate this? Well, obviously, you could do null checks before each check, but that starts to get ugly: 1: if (x.HasValue) 2: { 3: if (y.HasValue) 4: { 5: if (x < y) 6: { 7: Console.WriteLine("x < y"); 8: } 9: else if (x > y) 10: { 11: Console.WriteLine("x > y"); 12: } 13: else 14: { 15: Console.WriteLine("x == y"); 16: } 17: } 18: else 19: { 20: Console.WriteLine("x > y because y is null and x isn't"); 21: } 22: } 23: else if (y.HasValue) 24: { 25: Console.WriteLine("x < y because x is null and y isn't"); 26: } 27: else 28: { 29: Console.WriteLine("x == y because both are null"); 30: } Yes, we could probably simplify this logic a bit, but it’s still horrendous!  So what do we do if we want to consider null less than everything and be able to properly compare Nullable<T> wrapped value types? The key is the System.Nullable static class.  This class is a companion class to the System.Nullable<T> class and allows you to use a few helper methods for Nullable<T> wrapped types, including a static Compare<T>() method of the. What’s so big about the static Compare<T>() method?  It implements an IComparer compatible comparison on Nullable<T> types.  Why do we care?  Well, if you look at the MSDN description for how IComparer works, you’ll read: Comparing null with any type is allowed and does not generate an exception when using IComparable. When sorting, null is considered to be less than any other object. This is what we probably want!  We want null to be less than everything!  So now we can change our logic to use the Nullable.Compare<T>() static method: 1: int? x = null; 2: int? y = 100; 3:  4: if (Nullable.Compare(x, y) < 0) 5: { 6: // Yes! x is null, y is not, so x is less than y according to Compare(). 7: Console.WriteLine("x < y"); 8: } 9: else if (Nullable.Compare(x, y) > 0) 10: { 11: Console.WriteLine("x > y"); 12: } 13: else 14: { 15: Console.WriteLine("x == y"); 16: } Summary So, when doing math comparisons between two numeric values where one of them may be a null Nullable<T>, consider using the System.Nullable.Compare<T>() method instead of the comparison operators.  It will treat null less than any value, and will avoid logic consistency problems when relying on < returning false to indicate >= is true and so on. Tweet   Technorati Tags: C#,C-Sharp,.NET,Little Wonders,Little Pitfalls,Nulalble

    Read the article

  • What non-programming tools do programmers use?

    - by user828584
    I'm reading code complete with the intention of learning how to better structure my code, but I'm also learning a lot about how many aspects of programming something there are that aren't just writing the code. The book talks a lot about problem definition, determining the requirements, defining the structure, designing the code, etc. What tools are used for these non-writing steps of programming? Is there software that will help me design and plan out what I'm going to write before I do?

    Read the article

  • How to explain to a layperson the variance in programmer rates?

    - by Matt McCormick
    I recently talked to a guy that is looking for developers to build a product idea. He mentioned he has received interest from people but the rates have varied from $20-120/hr. This project he estimates should take 3-6 months and since he is non-technical, he is confused why there can be so much variance. I understand how I would choose someone but I am a developer and can gauge other people's work. How can I explain to him (in a non-biased way, if possible, as I will apply as well) about the variance in rates? Is there any good analogy that would help?

    Read the article

  • Are nullable types preferable to magic numbers?

    - by Matt H
    I have been having a little bit of a debate with a coworker lately. We are specifically using C#, but this could apply to any language with nullable types. Say for example you have a value that represents a maximum. However, this maximum value is optional. I argue that a nullable number would be preferable. My coworker favors the use of zero, citing precedent. Granted, things like network sockets have often used zero to represent an unlimited timeout. If I were to write code dealing with sockets today, I would personally use a nullable value, since I feel it would better represent the fact that there is NO timeout. Which representation is better? Both require a condition checking for the value meaning "none", but I believe that a nullable type conveys the intent a little bit better.

    Read the article

  • How do I mount Samba share as non-root user

    - by Android Eve
    Is there a step-by-step tutorial that instructs in detailed step-by-step how to smbmount a Samba share to be used by a non-root user on a Ubuntu 10.04 desktop? Note: there are numerous threads on Google search dealing with this seemingly new problem. Instructions that used to work on Ubuntu 8.04 (or an older version of smbfs) no longer work. I need something fresh, punctual and especially reproducible. Thanks.

    Read the article

  • What dangers await if I block non-standard, non-major-usa search engine bots from my USA only website?

    - by Ryan
    I noticed tons of bandwidth being used by non-USA search engine bots, so I began blocking them in an effort to save bandwidth and cpu cycles for actual users and the search engines they come from (Google, Bing, Yahoo, Ask, etc.). Other than potentially losing some international traffic (which isn't really important to us since all of our content is very USA-centric), what additional dangers should I be concerned about? I'm using a modified version of Jeff Starr's User Agent Blocklist

    Read the article

  • Null Or Empty Coalescing

    - by Latest Microsoft Blogs
    In my last blog post, I wrote about the proper way to check for empty enumerations and proposed an IsNullOrEmpty method for collections which sparked a lot of discussion. This post covers a similar issue, but from a different angle. A very long time ago Read More......(read more)

    Read the article

  • Insights From a Non-Geek Working With Technical Developers at a Software Startup

    Everyone is wired differently. Some people are artistic, some are leaders and some are highly technical. Most of the time, it is fairly difficult for these different types of people to communicate effectively and understand each others' limitations and strengths. This can be especially true if you find yourself working as a non-technical employee in a highly technical field such as software development.

    Read the article

  • Non-x86 Blade Server Buyer's Guide

    When it comes to blade servers, x86 is the most frequent architecture of choice. Bladed or not, however, x86 servers are not the perfect tool for every task. Non-x86 blade server options, while limited, fill many of the gaps that their x86 siblings leave.

    Read the article

  • Non-x86 Blade Server Buyer's Guide

    When it comes to blade servers, x86 is the most frequent architecture of choice. Bladed or not, however, x86 servers are not the perfect tool for every task. Non-x86 blade server options, while limited, fill many of the gaps that their x86 siblings leave.

    Read the article

  • Tech Article: Tired of Null Pointer Exceptions? Use Java SE 8's Optional!

    - by Tori Wieldt
    A wise man once said you are not a real Java programmer until you've dealt with a null pointer exception. The null reference is the source of many problems because it is often used to denote the absence of a value. Java SE 8 introduces a new class called java.util.Optional that can alleviate some of these problems. In the tech article "Tired of Null Pointer Exceptions? Use Java SE 8's Optional!" Java expert Raoul-Gabriel Urma shows you how to make your code more readable and protect it against null pointer exceptions. Urma explains "The purpose of Optional is not to replace every single null reference in your codebase but rather to help design better APIs in which—just by reading the signature of a method—users can tell whether to expect an optional value. In addition, Optional forces you to actively unwrap an Optional to deal with the absence of a value; as a result, you protect your code against unintended null pointer exceptions." Learn how to go from writing painful nested null checks to writing declarative code that is composable, readable, and better protected from null pointer exceptions. Read "Tired of Null Pointer Exceptions? Use Java SE 8's Optional!"

    Read the article

  • MySQL Unions/Subselects not utilizing keys from associated tables

    - by Brett
    I've noticed by doing EXPLAINs that when a MySQL union between two tables is used, mysql creates a temporary table, but the temp table does not use keys, so queries are slowed considerably. Here is an example: SELECT * FROM ( SELECT `part_number`, `part_manufacturer_clean`, `part_number_clean`, `part_heci`, `part_manufacturer`, `part_description` FROM `new_products` AS `a` UNION SELECT `part` as `part_number`, `manulower` as `part_manufacturer_clean`, `partdeluxe` as `part_number_clean`, `heci` as `part_heci`, `manu` as `part_manufacturer`, `description` as `part_description` FROM `warehouse` AS `b` ) AS `c` WHERE `part_manufacturer_clean` = 'adc' EXPLAIN yields this: id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY <derived2> ALL (NULL) (NULL) (NULL) (NULL) 17206 Using where 2 DERIVED a ALL (NULL) (NULL) (NULL) (NULL) 17743 3 UNION b ALL (NULL) (NULL) (NULL) (NULL) 5757 (NULL) UNION RESULT <union2,3> ALL (NULL) (NULL) (NULL) (NULL) (NULL) In this case, part_manufacturer_clean and manulower are keys in both tables. When I don't use the subselects and union, and just use one table, everything works fine. I'm not sure if the issue is with the union or with the subselects. Is there any way to union two tables and still use keys/indexes for performance?

    Read the article

  • Exim PanicLog has Non-Zero Size...?

    - by willbeeler
    I'm getting the following error from my Ubuntu server: exim paniclog /var/log/exim4/paniclog on (my server FQDN) has non-zero size, mail system might be broken. I found a solution on the web here. Basically, I just need erase the paniclog by entering the following code: sudo rm /var/log/exim4/paniclog So, I know how to get rid of the error, but I don't know how it started, and how to not let it happen again. Any explanation? Thanks in advance.

    Read the article

  • Online Press Releases Essential For Non-Profits

    An online Press Release has become a powerful tool to convey your message to a large and dispersed target audience. Where advertising serves as a form of direct self-promotion, a Press Release serves the same purpose but in a more subtle and informative manner. A PR for your non-profit should be used judiciously, when there is real newsworthy content to disseminate.

    Read the article

  • MySQL query works in PHPMyAdmin but not PHP

    - by Su4p
    I do not understand what's happening. I have a query in PHP who crashes -with a strange error-. When I copy/paste the exact same request in PHPMyAdmin it works as expected. What am I doing wrong here ? SELECT oms_patient.id, oms_patient.date, oms_patient.date_modif, date_modif, AES_DECRYPT(nom,"xxxxx") AS "Nom", AES_DECRYPT(prenom,"xxxxx") AS "Prénom usuel", DATE_FORMAT(ddn, "%d/%m/%Y") AS "Date de naissance", villeNaissance AS "Lieu de naissance (ville)", CONCAT(oms_departement.libelle,"(",id_departement,")") AS "Lieu de vie", CONCAT(oms_pays.libelle,"(",id_pays,")") AS "Pays", CONCAT(patientsexe.libelle,"(",id_sexe,")") AS "Sexe", CONCAT(patientprofession.libelle,"(",id_profession,")") AS "Profession", IF(asthme>0,"Oui","Non") AS "Asthme", IF(rhinite>0,"Oui","Non") AS "Rhinite", IF(bcpo>0,"Oui","Non") AS "BPCO", IF(insuffisanceResp>0,"Oui","Non") AS "Insuffisance respiratoire chronique", IF(chirurgieOrl>0,"Oui","Non") AS "Chirurgie ORL du ronflement", IF(autreChirurgie>0,"Oui","Non") AS "Autre chirurgie ORL", IF(allergies>0,"Oui","Non") AS "Allergies", IF(OLD>0,"Oui","Non") AS "OLD", IF(hypertensionArterielle>0,"Oui","Non") AS "Hypertension artérielle", IF(infarctusMyocarde>0,"Oui","Non") AS "Infarctus du myocarde", IF(insuffisanceCoronaire>0,"Oui","Non") AS "Insuffisance coronaire", IF(troubleRythme>0,"Oui","Non") AS "Trouble du rythme", IF(accidentVasculaireCerebral>0,"Oui","Non") AS "Accident vasculaire cérébral", IF(insuffisanceCardiaque>0,"Oui","Non") AS "Insuffisance cardiaque", IF(arteriopathie>0,"Oui","Non") AS "Artériopathie", IF(tabagismeActuel>0,"Oui","Non") AS "Tabagisme actuel", CONCAT(nbPaquetsActuel," ","PA") AS "", IF(tabagismeAncien>0,"Oui","Non") AS "Tabagisme ancien", CONCAT(nbPaquetsAncien," ","PA") AS "", IF(alcool>0,"Oui","Non") AS "Alcool (conso régulière)", IF(refluxGastro>0,"Oui","Non") AS "Reflux gastro-oesophagien", IF(glaucome>0,"Oui","Non") AS "Glaucome", IF(diabete>0,"Oui","Non") AS "Diabète", CONCAT(patienttypeDiabete.libelle,"(",id_typeDiabete,")") AS "", IF(hypercholesterolemie>0,"Oui","Non") AS "Hypercholestérolémie", IF(hypertriglyceridemie>0,"Oui","Non") AS "Hypertriglycéridémie", IF(dysthyroidie>0,"Oui","Non") AS "Dysthyroïdie", IF(depression>0,"Oui","Non") AS "Dépression", IF(sedentarite>0,"Oui","Non") AS "Sédentarité", IF(syndromeDApneesSommeil>0,"Oui","Non") AS "SAS", IF(obesite>0,"Oui","Non") AS "Obésité", IF(dysmorphieFaciale>0,"Oui","Non") AS "Dysmorphie faciale", TextObservations AS "", id_user FROM oms_patient LEFT JOIN oms_departement ON oms_departement.id = id_departement LEFT JOIN oms_pays ON oms_pays.id = id_pays LEFT JOIN patientsexe ON patientsexe.id = id_sexe LEFT JOIN patientprofession ON patientprofession.id = id_profession LEFT JOIN patienttypeDiabete ON patienttypeDiabete.id = id_typeDiabete WHERE oms_patient.id=1 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'small"(conso régulière)", IF(refluxGastro0,"Oui","Non") as "Reflux ga' at line 1 "near 'small" <-- where is small o_O The PHP code isn't really relevant cause you won't see a lot. $db = mysql_connect(); mysql_select_db();//TODO SWITCH TO PDO mysql_query("SET NAMES UTF8"); $fields = $form->getFields($form); $settingsForm = $form->getSettings(); $sql = 'SELECT oms_patient.id,oms_patient.date,oms_patient.date_modif,'; foreach ($fields as $field) { if (!$field->isMultiSelect()) { $field->select_full(&$sql, 'oms_patient', null); } } if (isset($settingsForm['linkTo'])) { $idLinkTo = 'id_' . str_replace('oms_', '', $settingsForm['linkTo']); $sql .= $idLinkTo; } $sql.=' FROM oms_patient'; foreach ($fields as $field) { if (!$field->isMultiSelect() && $field->getTable('oms_patient')) { $sql .=' LEFT JOIN ' . $field->getTable('oms_patient') . ' ON ' . $field->getTable('oms_patient') . '.id = '.$field->getFieldName().' '; } } $sql.=' where oms_patient.id=' . $this->m_settings['e']; $result = mysql_query($sql) or die('Erreur SQL !<br>' . $sql . '<br>' . mysql_error()); $data = mysql_fetch_assoc($result); var_dump of $sql string(2663) "SELECT oms_patient.id,oms_patient.date,oms_patient.date_modif,date_modif,AES_DECRYPT(nom,"xxxxx") as "Nom",AES_DECRYPT("prenom","xxxxx") as "Prénom usuel",DATE_FORMAT(ddn, "%d/%m/%Y") as "Date de naissance",villeNaissance as "Lieu de naissance (ville)",CONCAT(oms_departement.libelle,"(",id_departement,")") as "Lieu de vie",CONCAT(oms_pays.libelle,"(",id_pays,")") as "Pays",CONCAT(patientsexe.libelle,"(",id_sexe,")") as "Sexe",CONCAT(patientprofession.libelle,"(",id_profession,")") as "Profession", IF"... can't go further to see what is in the output after the "..." <-- if you have an idea

    Read the article

  • Efficiency of checking for null varbinary(max) column ?

    - by Moe Sisko
    Using SQL Server 2008. Example table : CREATE table dbo.blobtest (id int primary key not null, name nvarchar(200) not null, data varbinary(max) null) Example query : select id, name, cast((case when data is null then 0 else 1 end) as bit) as DataExists from dbo.blobtest Now, the query needs to return a "DataExists" column, that returns 0 if the blob is null, else 1. This all works fine, but I'm wondering how efficient it is. i.e. does SQL server need to read in the whole blob to its memory, or is there some optimization so that it just does enough reads to figure out if the blob is null or not ? (FWIW, the sp_tableoption "large value types out of row" option is set to OFF for this example).

    Read the article

  • How to deserialize null array to null in c#?

    - by Aen Sidhe
    Here is my class: public class Command { [XmlArray(IsNullable = true)] public List<Parameter> To { get; set; } } When I serialize an object of this class: var s = new XmlSerializer(typeof(Command)); s.Serialize(Console.Out, new Command()); it prints as expected (xml header and default MS namespaces are omitted): <Command><To xsi:nil="true" /></Command> When I took this xml and tried to deserialize it I got stucked, because it always print "Not null": var t = s.Deserialize(...); if (t.To == null) Console.WriteLine("Null"); else Console.WriteLine("Not null"); How to force deserializer to make my list null, if it is null in xml?

    Read the article

  • Liqn to sql null-able value in query

    - by msony
    I need get all items what have no categories int? categoryId = null; var items=db.Items.Where(x=>x.CategoryId==categoryId); this code generate in where: where CategoryId=null instead of where CategoryId is null ok, when i write var items=db.Items.Where(x=>x.CategoryId==null); in my sql profiler it works: where CategoryId is null BUT when i do this HACK it doesn't: var items=db.Items.Where(x=>x.CategoryId==(categoryId.HasValue ? categoryId : null)); so what's the problem? is there by in L2S?

    Read the article

  • Posting null values via AJAX

    - by nickf
    Using the jQuery $.post function, if you send a null value, it arrives at the server side as "null". Example: Javascript: $.post('test.php', { foo : null }); PHP: var_dump($_POST['foo']); // string(4) "null" I understand why this is so, but was wondering the best way to work around the limitation? Should you: Loop through all the variables in JS before you send them and replace with an empty string? Interpret "null" as null on the server side? Don't send the variable at all? Something else?

    Read the article

  • non static method cannot be referenced from a static context.

    - by David
    First some code: import java.util.*; ... class TicTacToe { ... public static void main (String[]arg) { Random Random = new Random() ; toerunner () ; // this leads to a path of methods that eventualy gets us to the rest of the code } ... public void CompTurn (int type, boolean debug) { ... boolean done = true ; int a = 0 ; while (!done) { a = Random.nextInt(10) ; if (debug) { int i = 0 ; while (i<20) { System.out.print (a+", ") ; i++; }} if (possibles[a]==1) done = true ; } this.board[a] = 2 ; } ... } //to close the class Here is the error message: TicTacToe.java:85: non-static method nextInt(int) cannot be referenced from a static context a = Random.nextInt(10) ; ^ What exactly went wrong? What does that error message "non static method cannot be referenced from a static context" mean?

    Read the article

< Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >