VENTI-LOG(2)                                         VENTI-LOG(2)

     NAME
          VtLog, VtLogChunk, vtlog, vtlogclose, vtlogdump, vtlognames,
          vtlogopen, vtlogprint, vtlogremove, vtlogopen, ventilogging
          - Venti logs

     SYNOPSIS
          #include <u.h>
          #include <libc.h>
          #include <venti.h>

          VtLog* vtlogopen(char *name, uint size);

          void   vtlogprint(VtLog *log, char *fmt, ...);

          void   vtlogclose(VtLog *log);

          void   vtlog(char *name, char *fmt, ...);

          void   vtlogremove(char *name);

          char** vtlognames(int *n);

          void   vtlogdump(int fd, VtLog *log);

          extern int ventilogging;    /* default 0 */

          extern char *VtServerLog;    /* "libventi/server" */

     DESCRIPTION
          These routines provide an in-memory circular log structure
          used by the Venti library and the Venti server to record
          events for debugging purposes.  The logs are named by UTF
          strings.

          Vtlogopen returns a reference to the log with the given name
          . If a log with that name does not exist and size is non-
          zero, vtlogopen creates a new log capable of holding at
          least size bytes and returns it.  Vtlogclose releases the
          reference returned by vtlogopen.

          Vtlogprint writes to log, which must be open.

          Vtlog is a convenient packaging of vtlogopen followed by
          vtlogprint and vtlogclose.

          Vtlogremove removes the log with the given name, freeing any
          associated storage.

          Vtlognames returns a list of the names of all the logs.  The
          length of the list is returned in *n.  The list should be

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     VENTI-LOG(2)                                         VENTI-LOG(2)

          freed by calling vtfree on the returned pointer.  The
          strings in the list will be freed by this call as well.  (It
          is an error to call vtfree on any of the strings in the
          list.)

          Vtlogdump prints log, which must be open, to the file
          descriptor fd.

          If ventilogging is set to zero (the default), vtlognames and
          vtlogdump can inspect existing logs, but vtlogopen always
          returns nil and vtlog is a no-op.  The other functions are
          no-ops when passed nil log structures.

          The server library (see venti-conn(2) and venti-server(2))
          writes debugging information to the log named VtServerLog,
          which defaults to the string `libventi/server'.

     SOURCE
          /sys/src/libventi

     SEE ALSO
          venti(2), venti(8)

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