while -- Command

Execute commands repeatedly
while sequence1 [do sequence2] done

The shell construct while controls  a loop.  It first executes the commands
in sequence1. If  the exit status is zero, the  shell executes the commands
in the optional sequence2 and repeats  the process until the exit status of
sequence1 is nonzero.  Because the shell recognizes a reserved word only as
the unquoted first word of a  command, both do and done must occur unquoted
at the start of a line or preceded by `;'.

The shell  commands break and  continue may be  used to alter  control flow
within a while  loop.  The until construct has the  same form as while, but
the sense of the test is reversed.

The shell executes while directly.

See Also

break,
commands,
continue,
ksh,
sh,
test,
until

© 2012 by Stephen A. Ness