mem(CMD) 19 June 1992 mem(CMD) Name mem - display the amount of used and free memory in your system Syntax mem [/program|/debug|/classify] To display the status of your system's used and free memory, use the fol- lowing syntax: mem Description You can use the mem command to display information about allocated memory areas, free memory areas, and programs that are currently loaded into memory. Switches /program Displays the status of programs that are currently loaded into memory. You cannot use the /program switch with the /debug switch or the /classify switch. You can abbreviate /program as /p. /debug Displays the status of currently loaded programs and of inter- nal drivers, and displays other programming information. You cannot use the /debug switch with the /program switch or the /classify switch. You can abbreviate /debug as /d. /classify Displays the status of programs loaded into conventional memory and the upper memory area. This switch lists the size of each program in decimal and hexadecimal notation, provides a summary of memory use, and lists the largest memory blocks that are available. You cannot use the /classify switch with the /pro- gram switch or the /debug switch. You can abbreviate /classify as /c. Notes Displaying memory status MS-DOS displays the status of extended memory only if you have installed memory above the 1-megabyte (MB) boundary in your system. MS-DOS dis- plays the status of expanded memory only if you use expanded memory that conforms to version 4.0 of the Lotus/Intel/Microsoft Expanded Memory Specification (LIM EMS). Allocating extended memory To allocate Interrupt 15h memory and XMS memory at the same time, use the /int15 switch when you load the HIMEM.SYS device driver. Example Suppose your system has both expanded memory and extended memory. To dis- play the status of your system's total memory-conventional, expanded, extended-and to display a list of programs currently loaded into memory, type the following command: mem /program The results might look similar to the following: Address Name Size Type ------- -------- ------ ------ 000000 000400 Interrupt Vector 000400 000100 ROM Communication Area 000500 000200 DOS Communication Area 000700 IO 000A80 System Data 001180 MSDOS 0014F0 System Data 002670 IO 006280 System Data HIMEM 0004A0 DEVICE= EMM386 002410 DEVICE= DISPLAY 002050 DEVICE= 0005D0 FILES= 000100 FCBS= 000200 BUFFERS= 0008F0 LASTDRIVE= 000740 STACKS= 008900 MSDOS 000040 System Program 008950 COMMAND 000940 Program 0092A0 MSDOS 000040 -- Free -- 0092F0 COMMAND 000200 Environment 009500 MEM 000190 Environment 0096A0 NISAMR 001FB0 Program 00B660 MEM 0135A0 Program 01EC10 MSDOS 0813D0 -- Free -- 09FFF0 MSDOS 028010 System Program 0C8010 MSDOS 000040 -- Free -- 0C8060 MOUSE 003A80 Program 0CBAF0 MSDOS 000190 -- Free -- 0CBC90 MSDOS 000AE0 -- Free -- 0CC780 XNSBIOS 000180 Environment 0CC910 XNSBIOS 002610 Program 0CEF30 SESSION 000180 Environment 0CF0C0 PRTSC 000180 Environment 0CF250 PRTSC 000320 Program 0CF580 DOSKEY 000FE0 Program 0D0570 MSDOS 007A60 -- Free -- 0D7FE0 MSDOS 008020 System Program 0E0010 IO 0069B0 System Data VT52 001060 DEVICE= SMARTDRV 005930 DEVICE= 0E69D0 SESSION 000410 Program 0E6DF0 REDIR 009200 Program 656384 bytes total conventional memory 655360 bytes available to MS-DOS 608640 largest executable program size 3145728 bytes total contiguous extended memory 0 bytes available contiguous extended memory 1027072 bytes available XMS memory MS-DOS resident in High Memory Area Total conventional memory is the amount of memory on your computer con- ventional memory MS-DOS has for operating your computer, including the memory it needs for itself. Largest executable program size is the larg- est contiguous block of conventional memory available for a program. Total EMS memory (not shown in the preceding example) is the amount of expanded memory on your computer. Free EMS memory (not shown in the preceding example) is the amount of expanded memory available for pro- grams. If you use EMM386 to simulate expanded memory, that memory appears in these two values. Total contiguous extended memory is the amount of memory beyond the 1- megabyte (MB) boundary on your computer. Available contiguous extended memory is the extended memory available for the Interrupt 15h interface. This memory is not being managed by an extended-memory manager, such as HIMEM.SYS. Some older programs use this different extended-memory scheme. Available XMS memory is memory that is being managed by an extended-mem- ory manager, such as HIMEM.SYS, and that is available to programs that can use it. Related command For information about checking the amount of space available on a disk, see the chkdsk(CMD) command.