36 lines
695 B
Groff
36 lines
695 B
Groff
.Dd 2015-10-08
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.Dt FLOCK 1
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.Os sbase
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.Sh NAME
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.Nm flock
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.Nd tool to manage locks on files
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.Sh SYNOPSIS
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.Nm
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.Op Fl nosux
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.Ar file
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.Ar cmd Op arg ...
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.Sh DESCRIPTION
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.Nm
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is used to manage advisory locks on open files.
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It is commonly used to prevent long running cron jobs from running in
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parallel.
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If
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.Ar file
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does not exist, it will be created.
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.Sh OPTIONS
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.Bl -tag -width Ds
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.It Fl n
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Set non-blocking mode on the lock.
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Fail immediately if the lock cannot be acquired.
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.It Fl o
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Close the file descriptor before exec to avoid having the exec'ed
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program holding on to the lock.
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.It Fl s
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Acquire a shared lock.
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.It Fl u
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Release the lock.
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.It Fl x
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Acquire an exclusive lock.
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This is the default.
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.El
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