diff options
Diffstat (limited to 'Doc/Zsh/params.yo')
| -rw-r--r-- | Doc/Zsh/params.yo | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/Doc/Zsh/params.yo b/Doc/Zsh/params.yo index 02ce796a9..69298855f 100644 --- a/Doc/Zsh/params.yo +++ b/Doc/Zsh/params.yo @@ -926,7 +926,9 @@ referenced or seeded in the parent shell in between subshell invocations. ) vindex(SECONDS) item(tt(SECONDS) <S>)( -The number of seconds since shell invocation. If this parameter +The number of seconds since shell invocation. On most platforms, this +is a monotonic value, so it is not affected by NTP time jumps or other +clock changes (though it may be affected by slewing). If this parameter is assigned a value, then the value returned upon reference will be the value that was assigned plus the number of seconds since the assignment. @@ -936,8 +938,10 @@ be changed using the tt(typeset) command. The type may be changed only to one of the floating point types or back to integer. For example, `tt(typeset -F SECONDS)' causes the value to be reported as a floating point number. The -value is available to microsecond accuracy, although the shell may -show more or fewer digits depending on the use of tt(typeset). See +value is nominally available to nanosecond precision, although this +varies by platform (and probably isn't accurate to 1 ns regardless), +and the shell may show more or fewer digits depending on the +use of tt(typeset). See the documentation for the builtin tt(typeset) in ifzman(zmanref(zshbuiltins))\ ifnzman(noderef(Shell Builtin Commands)) for more details. @@ -1735,8 +1739,12 @@ A star may be inserted between the percent sign and flags printing time (e.g., `tt(%*E)'); this causes the time to be printed in `var(hh)tt(:)var(mm)tt(:)var(ss)tt(.)var(ttt)' format (hours and minutes are only printed if they are not zero). -Alternatively, `tt(m)' or `tt(u)' may be used (e.g., `tt(%mE)') to produce -time output in milliseconds or microseconds, respectively. +Alternatively, `tt(m)', `tt(u)', or `tt(n)' may be used (e.g., +`tt(%mE)') to produce time output in milliseconds, microseconds, or +nanoseconds, respectively. Note that some timings on some platforms +are not actually nanosecond-precise (nor accurate to 1 ns when +they are); in fact on many systems user and kernel times are not +even microsecond-precise. ) vindex(TMOUT) item(tt(TMOUT))( |