v/vlib/os/fd.c.v

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module os
// file descriptor based operations:
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// close filedescriptor
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pub fn fd_close(fd int) int {
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if fd == -1 {
return 0
}
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return C.close(fd)
}
pub fn fd_write(fd int, s string) {
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if fd == -1 {
return
}
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mut sp := s.str
mut remaining := s.len
for remaining > 0 {
written := C.write(fd, sp, remaining)
if written < 0 {
return
}
remaining = remaining - written
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sp = unsafe { voidptr(sp + written)}
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}
}
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// read from filedescriptor, block until data
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pub fn fd_slurp(fd int) []string {
mut res := []string{}
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if fd == -1 {
return res
}
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for {
s, b := fd_read(fd, 4096)
if b <= 0 {
break
}
res << s
}
return res
}
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// read from filedescriptor, don't block
// return [bytestring,nrbytes]
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pub fn fd_read(fd int, maxbytes int) (string, int) {
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if fd == -1 {
return '', 0
}
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unsafe {
mut buf := malloc_noscan(maxbytes + 1)
nbytes := C.read(fd, buf, maxbytes)
if nbytes < 0 {
free(buf)
return '', nbytes
}
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buf[nbytes] = 0
return tos(buf, nbytes), nbytes
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}
}