Conditional execution

Both OS/2 and NT offer a way to create your own one-time single-line "batch files" from the command line:

Conditional execution
Syntax	Description	Equivalent to
`command1 & command2`	Execute command2 after execution of command1 has finished	`command1 command2`
`command1 && command2`	Execute command2 only if execution of command1 has finished successfully	`command1 IF NOT ERRORLEVEL 1 command2`
`command1 \|\| command2`	Execute command2 only if execution of command1 has finished unsuccessfully	`command1 IF ERRORLEVEL 1 command2`

Some examples:

FORMAT A: /Q && COPY C:\DATA\*.* A:
will copy all files from C:\DATA to diskette IF and ONLY IF the format succeeds.

XCOPY C:\*.* D:\ /S 2>&1> NUL || ECHO Something terrible happened
will display your own custom error message if XCOPY fails.

page last uploaded: 23 November 2011, 19:49