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Wichert Akkerman76baf7c1999-02-19 00:21:36 +00001Even though SVR4 has truss, you may prefer using strace for a number
2of reasons. Not the least of which are portability and source code.
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4The main event loop is awkward on systems for which procfs isn't
5pollable. I think a pollable procfs is a Solaris invention so most SVR4
6systems have this weakness. On Solaris, strace runs as a single
7controlling process. This is a big improvement if you are debugging a
8lot of processes at once.
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10There is no thread support but it wouldn't be very difficult to add it.
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Wichert Akkerman9dbf1541999-11-26 13:11:29 +000012On UnixWare using the -f option to follow forked children sometimes shows
13many "unfinished" system calls as strace bounces between each runnable child.
14A crude workaround for this is available by adding
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16 #define POLL_HACK 1
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18to the config.h file. This forces strace to check whether the last process
19has finished a system call before polling other processes for events.
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Wichert Akkerman9ce1a631999-08-29 23:15:07 +000021Wichert Akkerman <wakkerma@debian.org>
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