49 lines
1.1 KiB
Groff
49 lines
1.1 KiB
Groff
.TH READ 2
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.UC 4
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.SH NAME
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read, write \- read / write syscalls
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.SH SYNOPSIS
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.nf
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.B #include <sys/types.h>
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.B #include <unistd.h>
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.B int read(int fildes, char *buf, off_t count);
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.B int write(int fildes, const char *buf, off_t count);
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.fi
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.SH DESCRIPTION
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.B read()
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attempts to read
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.I count
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bytes from open file descriptor
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.I filedes
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, storing them in the memory location pointed to by
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.I buf
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.
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.B write()
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works in the same fashion, only the bytes are written to the file descriptor.
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.B read
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and
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.B write()
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return the number of bytes successfully read from or written to the file
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descriptor, 0 on EOF, and a negative number on any other error condition.
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.SH ERRORS
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0 is returned on EOF
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.PP
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.B -EBADF
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is returned when an invalid
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.I filedes
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was used, the file was opened read only and a write was attempted,
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or the file was opened write only and a read was attempted.
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.PP
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.B -EINVAL
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is returned when the
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.B i_mode
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field of the inode is invalid.
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.SH FILES
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linux/fs/read_write.c
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.br
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/usr/include/linux/sys.h
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.br
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/usr/include/unistd.h
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.SH SEE ALSO
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fread(3), fwrite(3)
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