From: The second adds the LEGACY_PTY config option. Without it, with late 2.6 kernels /dev/ptyxx won't work. In fact, with those kernels, root_fs_toms does not work, because it's "unable to allocate TTY pair". And removes the dead option "UNIX98_PTY_COUNT" (just commented out for now). Signed-off-by: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton --- 25-akpm/arch/um/Kconfig_char | 57 +++++++++++++++++++++++++++++++++++++++---- 1 files changed, 53 insertions(+), 4 deletions(-) diff -puN arch/um/Kconfig_char~uml-adds-legacy_pty-config-option arch/um/Kconfig_char --- 25/arch/um/Kconfig_char~uml-adds-legacy_pty-config-option 2004-07-05 16:00:38.606151424 -0700 +++ 25-akpm/arch/um/Kconfig_char 2004-07-05 16:00:38.609150968 -0700 @@ -108,11 +108,60 @@ config SSL_CHAN config UNIX98_PTYS bool "Unix98 PTY support" - -config UNIX98_PTY_COUNT - int "Maximum number of Unix98 PTYs in use (0-2048)" - depends on UNIX98_PTYS + ---help--- + A pseudo terminal (PTY) is a software device consisting of two + halves: a master and a slave. The slave device behaves identical to + a physical terminal; the master device is used by a process to + read data from and write data to the slave, thereby emulating a + terminal. Typical programs for the master side are telnet servers + and xterms. + + Linux has traditionally used the BSD-like names /dev/ptyxx for + masters and /dev/ttyxx for slaves of pseudo terminals. This scheme + has a number of problems. The GNU C library glibc 2.1 and later, + however, supports the Unix98 naming standard: in order to acquire a + pseudo terminal, a process opens /dev/ptmx; the number of the pseudo + terminal is then made available to the process and the pseudo + terminal slave can be accessed as /dev/pts/. What was + traditionally /dev/ttyp2 will then be /dev/pts/2, for example. + + All modern Linux systems use the Unix98 ptys. Say Y unless + you're on an embedded system and want to conserve memory. + +config LEGACY_PTYS + bool "Legacy (BSD) PTY support" + default y + ---help--- + A pseudo terminal (PTY) is a software device consisting of two + halves: a master and a slave. The slave device behaves identical to + a physical terminal; the master device is used by a process to + read data from and write data to the slave, thereby emulating a + terminal. Typical programs for the master side are telnet servers + and xterms. + + Linux has traditionally used the BSD-like names /dev/ptyxx + for masters and /dev/ttyxx for slaves of pseudo + terminals. This scheme has a number of problems, including + security. This option enables these legacy devices; on most + systems, it is safe to say N. + + +config LEGACY_PTY_COUNT + int "Maximum number of legacy PTY in use" + depends on LEGACY_PTYS default "256" + ---help--- + The maximum number of legacy PTYs that can be used at any one time. + The default is 256, and should be more than enough. Embedded + systems may want to reduce this to save memory. + + When not in use, each legacy PTY occupies 12 bytes on 32-bit + architectures and 24 bytes on 64-bit architectures. + +#config UNIX98_PTY_COUNT +# int "Maximum number of Unix98 PTYs in use (0-2048)" +# depends on UNIX98_PTYS +# default "256" config WATCHDOG bool "Watchdog Timer Support" _