how was the pipe(2) system call working in “traditional” Unix
This is what perldoc -f syscall says:
There's a problem with
syscall(SYS_pipe()): it returns the file
number of the read end of the pipe it creates, but there is no way
to retrieve the file number of the other end. You can avoid this
problem by usingpipeinstead.
However, that doesn't check out. syscall works with SYS_pipe just like with any other system call, and I'm perfectly able to retrieve both ends:
perl -e '
require "syscall.ph";
my $p = pack "i2";
syscall SYS_pipe(), $p;
print join(",", unpack "i2", $p), "n"
'
3,4
That was on linux, it's the same on openbsd, solaris, provided that you take care of some differences (on solaris, the system call is actually pipe2(2), so syscall 42, $p, 0).
A comment in fs/pipe.c in the linux kernel source says:
/*
* sys_pipe() is the normal C calling standard for creating
* a pipe. It's not the way Unix traditionally does this, though.
*/
So what was that "traditional" way? And are there any modern systems where that's still the case?
pipe history system-calls
asked 2 mins ago
CăcărăuCăcărău
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This is what perldoc -f syscall says:
There's a problem with
syscall(SYS_pipe()): it returns the file
number of the read end of the pipe it creates, but there is no way
to retrieve the file number of the other end. You can avoid this
problem by usingpipeinstead.
However, that doesn't check out. syscall works with SYS_pipe just like with any other system call, and I'm perfectly able to retrieve both ends:
perl -e '
require "syscall.ph";
my $p = pack "i2";
syscall SYS_pipe(), $p;
print join(",", unpack "i2", $p), "n"
'
3,4
That was on linux, it's the same on openbsd, solaris, provided that you take care of some differences (on solaris, the system call is actually pipe2(2), so syscall 42, $p, 0).
A comment in fs/pipe.c in the linux kernel source says:
/*
* sys_pipe() is the normal C calling standard for creating
* a pipe. It's not the way Unix traditionally does this, though.
*/
So what was that "traditional" way? And are there any modern systems where that's still the case?
pipe history system-calls
asked 2 mins ago
CăcărăuCăcărău
1
New contributor
Căcărău is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
This is what perldoc -f syscall says:
There's a problem with
syscall(SYS_pipe()): it returns the file
number of the read end of the pipe it creates, but there is no way
to retrieve the file number of the other end. You can avoid this
problem by usingpipeinstead.
However, that doesn't check out. syscall works with SYS_pipe just like with any other system call, and I'm perfectly able to retrieve both ends:
perl -e '
require "syscall.ph";
my $p = pack "i2";
syscall SYS_pipe(), $p;
print join(",", unpack "i2", $p), "n"
'
3,4
That was on linux, it's the same on openbsd, solaris, provided that you take care of some differences (on solaris, the system call is actually pipe2(2), so syscall 42, $p, 0).
A comment in fs/pipe.c in the linux kernel source says:
/*
* sys_pipe() is the normal C calling standard for creating
* a pipe. It's not the way Unix traditionally does this, though.
*/
So what was that "traditional" way? And are there any modern systems where that's still the case?
pipe history system-calls
asked 2 mins ago
CăcărăuCăcărău
1
New contributor
Căcărău is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
This is what perldoc -f syscall says:
There's a problem with
syscall(SYS_pipe()): it returns the file
number of the read end of the pipe it creates, but there is no way
to retrieve the file number of the other end. You can avoid this
problem by usingpipeinstead.
However, that doesn't check out. syscall works with SYS_pipe just like with any other system call, and I'm perfectly able to retrieve both ends:
perl -e '
require "syscall.ph";
my $p = pack "i2";
syscall SYS_pipe(), $p;
print join(",", unpack "i2", $p), "n"
'
3,4
That was on linux, it's the same on openbsd, solaris, provided that you take care of some differences (on solaris, the system call is actually pipe2(2), so syscall 42, $p, 0).
A comment in fs/pipe.c in the linux kernel source says:
/*
* sys_pipe() is the normal C calling standard for creating
* a pipe. It's not the way Unix traditionally does this, though.
*/
So what was that "traditional" way? And are there any modern systems where that's still the case?
pipe history system-calls
pipe history system-calls
asked 2 mins ago
CăcărăuCăcărău
1
New contributor
Căcărău is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 2 mins ago
CăcărăuCăcărău
1
New contributor
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asked 2 mins ago
CăcărăuCăcărău
1
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asked 2 mins ago
CăcărăuCăcărău
1
asked 2 mins ago
CăcărăuCăcărău
1
1
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