78 lines
1.4 KiB
Text
78 lines
1.4 KiB
Text
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.TH SYSCALL 1
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.SH NAME
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syscall \- test a system call
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.SH SYNOPSIS
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.B syscall
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[
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.B -osx
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]
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.I entry
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[
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.I arg ...
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]
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.SH DESCRIPTION
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.I Syscall
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invokes the system call
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.I entry
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with the given arguments.
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(Some functions, such as
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.I write
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and
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.IR read (2),
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although not strictly system calls, are valid
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.IR entries .)
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It prints the return value and the error string, if there was an error.
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An argument is either an integer constant as in C (its value is passed),
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a string (its address is passed),
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or the literal
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.B buf
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(a pointer to a 1MB buffer is passed).
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.PP
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If
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.B -o
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is given, the contents of the 1MB buffer are printed as a zero-terminated string
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after the system call is done.
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The
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.B -x
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and
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.B -s
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options are similar, but
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.B -x
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formats the data as hexadecimal bytes, while
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.B -s
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interprets the data as a
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.IR stat (5)
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message and formats it similar to the style of
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.B ls
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.B -lqm
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(see
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.IR ls (1)),
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with extra detail about the modify and access times.
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.SH EXAMPLES
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Write a string to standard output:
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.IP
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.EX
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syscall write 1 hello 5
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.EE
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.PP
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Print information about the file connected to standard input:
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.IP
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.EX
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syscall -s fstat 0 buf 1024
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.EE
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.SH SOURCE
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.B /sys/src/cmd/syscall
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.SH "SEE ALSO"
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Section 2 of this manual.
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.SH DIAGNOSTICS
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If
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.I entry
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is not known to
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.IR syscall ,
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the exit status is
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.LR unknown .
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If the system call succeeds, the exit status is null;
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otherwise the exit status is the string that
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.IR errstr (2)
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returns.
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