* Re: System calls in zsh
1998-04-23 19:45 System calls in zsh Nik Gervae
@ 1998-04-23 20:01 ` Mirar
1998-04-23 20:46 ` Dan Nelson
1 sibling, 0 replies; 3+ messages in thread
From: Mirar @ 1998-04-23 20:01 UTC (permalink / raw)
To: Nik Gervae; +Cc: zsh-workers
Nik Gervae <Nik@pdi.com> writes:
> Hello. I've been using zsh 3.0.0 on IRIX for a while here at work, and we
> just started an evaluation of shell script efficiency that prompted me to
> ask this. It seems that if you create an empty zsh script and run it, it
> invokes these system calls (which I got using "par -s -S"):
strace on linux sais:
| mistel% strace zsh -c '' 2>&1 | grep open
| open("/etc/ld.so.cache", O_RDONLY) = 4
| open("/usr/local/lib/libtermcap.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/lib/libtermcap.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/lib/libtermcap.so.2", O_RDONLY) = 4
| open("/usr/local/lib/libc.so.5", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/lib/libc.so.5", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/lib/libc.so.5", O_RDONLY) = 4
| open("/usr/share/locale/C/LC_MESSAGES", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/share/locale/C/LC_MONETARY", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/share/locale/C/LC_COLLATE", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/share/locale/C/LC_TIME", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/share/locale/C/LC_NUMERIC", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/usr/share/locale/iso_8859_1/LC_CTYPE", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/dev", O_RDONLY) = 4
| open("/dev/ttypc", O_RDWR) = 4
| open("/etc/nsswitch.conf", O_RDONLY) = 4
| open("/etc/passwd", O_RDONLY) = 4
| open("/dev", O_RDONLY) = 4
| open("/var/run/utmp", O_RDONLY) = 4
| open("/usr/share/locale/iso_8859_1/LC_CTYPE", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/etc/zshenv", O_RDONLY) = -1 ENOENT (No such file or directory)
| open("/home/mirar/.zshenv", O_RDONLY) = 4
| open("/etc/passwd", O_RDONLY) = 4
| open("/users/mirar/bin/zsh-compctl", O_RDONLY) = 4
| open("/home/mirar/bin", O_RDONLY) = 4
| open("/usr/local/bin", O_RDONLY) = 4
| open("/usr/local/share/bin", O_RDONLY) = 4
| open("/usr/bin", O_RDONLY) = 4
| open("/bin", O_RDONLY) = 4
| open("/dev/null", O_RDONLY) = 4
| mistel%
The first 10-or-so seems to be locale stuff, the next 8 is probably
tty stuff and finding my home directory (user directory).
The last 6 has someting with running the command '' to do.
(that's my path).
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: System calls in zsh
1998-04-23 19:45 System calls in zsh Nik Gervae
1998-04-23 20:01 ` Mirar
@ 1998-04-23 20:46 ` Dan Nelson
1 sibling, 0 replies; 3+ messages in thread
From: Dan Nelson @ 1998-04-23 20:46 UTC (permalink / raw)
To: Nik Gervae, zsh-workers
In the last episode (Apr 23), Nik Gervae said:
> Hello. I've been using zsh 3.0.0 on IRIX for a while here at work,
> and we just started an evaluation of shell script efficiency that
> prompted me to ask this. It seems that if you create an empty zsh
> script and run it, it invokes these system calls (which I got using
> "par -s -S"):
>
> exit : 1 times
> read : 12 times
> open : 12 times
> close : 11 times
[etc]
> Can anyone explain why read() and open() are called so many times for
> an empty shell script? The Bourne and Korn shells here invoke them
> twice each. zsh seems to be expending a bit more effort here than
> might be necessary.
Check to see which files are being opened and read. On FreeBSD, a
zsh -f -c '' opens the following:
/var/run/dev.db, /dev/tty, /etc/pwd.db, /etc/zshenv, /dev/null, and
takes .02 seconds from exec() to exit().
If you forgot to put a -f on your zsh commandline, it's probably
reading your zprofile, zshrc, zshenv, and zshrc files.
^ permalink raw reply [flat|nested] 3+ messages in thread