Get uptime in seconds or miliseconds on Unix like systems

Question

I need a method which can give me the number of miliseconds or seconds, elapsed since the system was started. I could parse /proc/uptime , but i can't afford to lose performance over this I/0 and parsing.

I'm using Linux and C/C++. Maybe i can put some Qt/Boost, but is better to be something native.

check post below, guy said it right, use sysinfo.h, i am unsure about you wanting milliseconds as `uptime` in sysinfo returns value in seconds — nikola-miljkovic, Dec 02 '11 at 13:49

Basile Starynkevitch · Accepted Answer · 2011-12-02T13:45:37.323

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Why cannot you afford reading /proc/uptime? It is not a real file so reading it should be quick (there is no real i/o involved, since the /proc/ filesystem contains pseudo-files). Did you benchmark its reading?

You might also call clock_gettime with CLOCK_MONOTONIC

NB. This is specific to Linux.

edited Dec 02 '11 at 13:45

answered Dec 02 '11 at 13:35

Basile Starynkevitch

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/proc files are not disk files, good answer. /proc lives in kernel. – jim mcnamara Dec 02 '11 at 15:38

score 4 · Answer 2 · answered Dec 02 '11 at 13:37

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You could try sysinfo.h.

answered Dec 02 '11 at 13:37

Franz

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Get uptime in seconds or miliseconds on Unix like systems

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