3 read, readn, write, pread, pwrite \- read or write file
10 long read(int fd, void *buf, long nbytes)
13 long readn(int fd, void *buf, long nbytes)
16 long write(int fd, void *buf, long nbytes)
19 long pread(int fd, void *buf, long nbytes, vlong offset)
22 long pwrite(int fd, void *buf, long nbytes, vlong offset)
28 from the offset in the file associated with
32 The offset is advanced by the number of bytes read.
36 bytes will be read; for example
37 if the file refers to the console, at most one line
39 In any event the number of bytes read is returned.
41 0 is conventionally interpreted as end of file.
44 is just like read, but does successive
48 have been read, or a read system call
49 returns a non-positive count.
54 bytes of data starting at
56 to the file associated with
59 The offset is advanced by the number of bytes written.
60 The number of characters actually written is returned.
61 It should be regarded as an error
62 if this is not the same as requested.
75 By combining the operations in a single atomic call, they more closely
80 permit multiprocess programs to execute multiple concurrent
81 read and write operations on the same file descriptor
84 .B /usr/local/plan9/src/libc/9syscall
86 .B /usr/local/plan9/src/libc/port/readn.c