The Set- procedures allow the user to attach values to certain environment variables. The Get- functions enable one to obtain the current values of these variables.

SetAssertions(b) : BoolElt ->

GetAssertions() : -> BoolElt

Controls the checking of assertions (see AssertAttribute in the chapter on the language). Default is SetAssertions(true).

GetAutoColumns() : -> BoolElt

If enabled, the IO system will try to determine the number of columns in the window by using ioctl(); when a window change or a stop/cont occurs, the Columns variable (below) will be automatically updated. If disabled, the Columns variable will only be changed when explicitly done so by SetColumns. Default is SetAutoColumns(true).

GetBeep() : -> BoolElt

Controls `beeps'. Default is SetBeep(true).

GetColumns() : -> RngIntElt

Controls the number of columns used by the IO system. This affects the line editor and the output system. (As explained above, if AutoColumns is on, this variable will be automatically determined.) The number of columns will determine how words are wrapped. If set to 0, word wrap is not performed. The default value is SetColumns(80) (unless SetAutoColumns(true)).

Returns the current directory as a string. (Use ChangeDirectory(s) to change the working directory.)

Set to true or false according to whether or not input from external files should also be sent to standard output.

GetHistorySize() : ->

Controls the number of lines saved in the history. If the number is set to 0, no history is preserved.

GetIgnorePrompt() : -> BoolElt

Controls the option to ignore the prompt to allow the pasting of input lines back in. If enabled, any leading '>' characters (possibly separated by white space) are ignored by the history system when the input file is a terminal. Default is SetIgnorePrompt(false).

GetIndent() : -> RngIntElt

Controls the indentation level for formatting output. The default is SetIndent(4).

GetLibraries() : -> MonStgElt

Controls the Magma library directories, via environment variable MAGMA_LIBRARIES. The procedure SetLibraries takes a string, which will be taken as the (colon-separated) list of sub-directories in the library root directory for the libraries; the function GetLibraryRoot returns the current value as a string. These directories will be searched when you try to load a file; note however that first the directories indicated by the current value of your path environment variable MAGMA_PATH will be searched. See SetLibraryRoot for the root directory.

GetLibraryRoot() : -> MonStgElt

Controls the root directory for the Magma libraries, via the environment variable MAGMA_LIBRARY_ROOT. The procedure SetLibraryRoot takes a string, which will be the absolute pathname for the root of the libraries; the function GetLibraryRoot returns the current value as a string. See also SetLibraries

GetLineEditor() : BoolElt ->

Controls the line editor. Default is SetLineEditor(true).

    Overwrite: BoolElt                  Default: false

UnsetLogFile() : ->

Procedure. Set the log file to be the file specified by the string F: all output will be sent to this log file as well as to the terminal. If a log file is already in use, it is closed and F is used instead. The parameter Overwrite can be used to indicate that the file should be emptied before writing output on it; by default the file is appended.

GetMemoryExtensionSize() : -> RngIntElt

Set the minimum number of bytes used by the memory manager when it has to extend the process arena. Default is SetMemoryExtensionSize(100000). (May be overridden by the environment variable MAGMA_MEMORY_EXTENSION_SIZE.)

GetMemoryLimit() : -> RngIntElt

Set the soft limit (in bytes) of the memory which the memory manager will allocate (no soft limit if 0). Default is SetMemoryLimit(0).

    Overwrite: BoolElt                  Default: false

UnsetOutputFile() : ->

Start/stop redirecting all Magma output to a file (specified by the string F). The parameter Overwrite can be used to indicate that the file should be emptied before writing output on it.

GetPath() : -> MonStgElt

Controls the path by which the searching of files is done. The path consists of a colon separated list of directories which are searched in order ("." implicitly assumed at the front). Tilde expansion is done on each directory. (May be overridden by the environment variable MAGMA_PATH.)

GetPrintLevel() : -> MonStgElt

Controls the global printing level, which is one of "Minimal", "Magma", "Maximal", "Default". Default is SetPrintLevel("Default").

GetPrompt() : -> MonStgElt

Controls the terminal prompt (a string). Expansion of the following % escapes occurs:

• The character %
• The current history line number.
• The parser `state': when a new line is about to be read while the parser has only seen incomplete statements, the state consists of a stack of words like "if", "while", indicating the incomplete statements.
• Like %S except that only the topmost word is displayed.

Default is SetPrompt("%S> ").

GetRows() : -> RngIntElt

Controls the number of rows in a page used by the IO system. This affects the output system. If set to 0, paging is not performed. Otherwise a prompt is given after the given number of rows for a new page. The default value is SetRows(0).

GetSeed() : -> RngIntElt

Controls the seed for pseudo-random number generation. (Pseudo-random quantities are used in several Magma algorithms, and may also be generated explicitly by some intrinsics.) The seed should be in the range 1 to (2 ^ (31) - 2) inclusive.

SetVerbose(s, b) : MonStgElt, BoolElt ->

GetVerbose(s) : MonStgElt -> RngIntElt

By turning verbose printing on for certain modules within Magma, some information on computations that are performed can be obtained. Here the argument s must be a string. The verbosity may have different levels. An integer for the second argument selects the appropriate level. A second argument of 0 or false means no verbosity. A boolean value of true for the second argument selects level 1. Currently the following options are available (together with their maximal levels):

AddRelation (1)        CosetTable (1)         OnanScott (1)
AddStrongGenerator (1) Decompose (1)          Orbits  (1)
Backtrack (1)          Derived (1)            Partition  (1)
BaseChange (1)         ECM (1)                Perm (1)
Berlekamp (1)          Endo (1)               PolyBerlekamp (1)
Blocks (1)             Gmodule (1)            PolyHensel  (1)
ChiefSeries (1)        Hom (1)                PolyZFactorize (1)
Chtr (1)               HomSylow (1)           PolyZSqfreeFactorize (1)
ClassMatrix (1)        InitializeBase (1)     RandomSchreier (1)
Classes (1)            InthdlGcd (1)          STCS  (1)
Code (1)               IsAltsym (1)           Schreier (1)
Cohomology (1)         MatOrder (1)           Smith (1)
Combine (1)            MaximalSubmodules (1)  Socle (1)
CommutatorSubgroup (1) Meataxe (1)            SubmoduleLattice (2)
CompositionFactors (1) NormalClosure (1)      Sylow (1)
Conj (1)               NormalLattice (1)      Verify (1)

Default is SetVerbose(s, false) on each of these.

There are also 5 slots available for user-defined verbose flags. The flags can be set in user programs by SetVerbose("Usern", true) where n should be one of 1, 2, 3, 4, 5, and the current setting is returned by GetVerbose("Usern").

GetViMode() : -> BoolElt

Controls the type of line editor used: Emacs (false) or VI style. Default is SetViMode(false).

List all identifiers that have have been assigned to.

List all identifiers that have been assigned to with their values.

Procedure to list a short description as well as the input and output arguments for all intrinsic functions, procedures and operators having objects from category C among its arguments. Use ListCategories for the names of the categories.

ListTypes() : ->

Procedure to list the (abbreviated) names for all available categories in Magma.