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VARSYM(1)	       DragonFly General Commands Manual	     VARSYM(1)

NAME

varsym -- get and set user and system-wide variables for variant symlinks

SYNOPSIS

varsym [-adpqsux] [var[=data] ...] varsym -x [var[=data] ...] command args

DESCRIPTION

The varsym program manages user and system-wide variables. These vari- ables are typically used by the system to resolve variant symlinks but may also be used generally. For each operand set, modify, retrieve, or delete the specified variable. By default variables specified without data are retrieved and variables specified with data are set. Variables may be set to empty. -a List all variables at the specified level. Note that per- process variables override per-user variables and per-user variables override system-wide variables. By default, per- user variables are listed. -d Delete mode. The specified variables are deleted. Any specified data is ignored. -p This option causes variables to be set on a per-process basis and restricts retrievals to process-specific vari- ables. Note that since varsym is run as its own process, using this option to set a variable will not affect your shell's namespace. Instead you might want to use the -x option to set local varsyms and exec a command. -q Quiet mode. When retrieving a variable only its data is printed. -s This option causes variables to be set system-wide and restricts retrievals to system-specific variables. -u This option causes variables to be set on a per-user-id basis and restricts retrievals to user-specific variables. This is the default unless -x is used. -x This option causes variables to be set only within the varsym process and its children, and also allows you to specify a command and arguments to exec after the var=data specifications.

EXIT STATUS

The varsym utility exits with one of the following values: 0 No errors occurred. 1 A requested variable could not be found 2 A requested variable could not be set

SEE ALSO

ln(1), varsym(2), varsym.conf(5) DragonFly 5.3 September 27, 2009 DragonFly 5.3 VARSYM(2) DragonFly System Calls Manual VARSYM(2)

NAME

varsym_get, varsym_set, varsym_list -- variant symlink variables

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <unistd.h> #include <sys/varsym.h> int varsym_get(int mask, const char *wild, char *buf, int bufsize); int varsym_set(int level, const char *name, const char *data); int varsym_list(int level, char *buf, int maxsize, int *marker);

DESCRIPTION

The varsym_get() system call retrieves the value of the first variable whose left side matches wild and return the value in buf. Bufsize speci- fies the length of the buffer and mask can be used to further restrict the search to variables of certain type. A value of VARSYM_ALL_MASK will search all variables (see below for other mask definitions). Varsym_set() sets the variable name of type level to the value pointed to by data. The varsym_list() system call fills the buffer buf with variable settings for the specified level. A maximum of maxsize bytes of settings are returned and marker is set to the actual number of name/value pairs read, or -1 if no more remain. Varsym_list() must be called repeatedly until marker is -1 if all settings are to be retrieved. The format of the buf- fer is ``\000name\000value\000name\000value...''. The following varsym levels (and masks) are defined in <sys/varsym.h>: VARSYM_PROC (VARSYM_PROC_MASK) Per-process variables. VARSYM_SYS (VARSYM_SYS_MASK) System wide variables. VARSYM_PRISON Used internally.

RETURN VALUES

The varsym_get() and varsym_set() functions return the value 0 if suc- cessful; otherwise the value -1 is returned and the global variable errno is set to indicate the error. The varsym_list() function returns the number of bytes read if success- ful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

ERRORS

The varsym system calls will fail when one of the following occurs: [EINVAL] An invalid level was specified. [ENOENT] A variable could not be found. [EOVERFLOW] Insufficient space for storing variable values was specified.

SEE ALSO

varsym(1)

HISTORY

The varsym system calls first appeared in DragonFly 1.0.

AUTHORS

The varsym system calls were written by Matthew Dillon and this manual page was written by Sascha Wildner. DragonFly 5.3 February 21, 2008 DragonFly 5.3

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