GWBASIC User's Manual

GW-BASIC User's Guide
SHELL Statement
Purpose:
To load and execute another program or batch file. When the program finishes, control returns to
the GW-BASIC program at the statement following the SHELL statement. A program executed
under control of GW-BASIC is referred to as a child process.
Syntax:
SHELL [string]
Comments:
string is a valid string expression containing the name of a program to run and (optionally)
command arguments.
The program name in string may have any extension that MS-DOS COMMAND.COM supports.
If no extension is supplied, COMMAND will look for a .COM file, then an .EXE file, and finally,
a .BAT file. If none is found, SHELL will issue a "File not found" error.
Any text separated from the program name by at least one blank space will be processed by
COMMAND as program parameters.
GW-BASIC remains in memory while the child process is running. When the child process
finishes, GW-BASIC continues at the statement following the SHELL statement.
SHELL with no string will go to MS-DOS. You may now do anything that COMMAND allows.
When ready to return to GW-BASIC, type the MS-DOS command EXIT.
Examples:
SHELL
A>DIR
A>EXIT
Write some data to be sorted, use SHELL SORT to sort it, then read the sorted data to write a
report.
10 OPEN "SORTIN.DAT" FOR OUTPUT AS #1
20 'write data to be sorted
.
.
.
1000 CLOSE 1
1010 SHELL "SORT SORTOUT.DAT"
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