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BEGIN {
LINT = 1
# `%.*s' used for input file and for output file
print "hi" > "f1"
fflush("f1")
getline x < "f1"
print close("f1")
print close("f1")
fflush()
# `%.*s' used for input file and input pipe
# `%.*s' used for input file and two-way pipe
# `%.*s' used for input pipe and two-way pipe
getline data3 < "echo hello"
"echo hello" |& getline data2
"echo hello" | getline data
print data, data2, data3
print close("echo hello")
print close("echo hello")
print close("echo hello")
fflush()
# `%.*s' used for input file and output pipe
getline x < "cat"
print "foo" | "cat"
print close("cat")
print close("cat")
fflush()
# unnecessary mixing of `>' and `>>' for file `%.*s'
print "foo" > "f2"
print "bar" >> "f2"
print close("f2")
print close("f2") # -1 expected here
fflush()
# `%.*s' used for input pipe and output file
"echo hello" | getline junk
print "hello" > "echo hello"
print close("echo hello")
print close("echo hello")
fflush()
# `%.*s' used for output file and output pipe
# `%.*s' used for output file and two-way pipe
# `%.*s' used for output pipe and two-way pipe
# Not doing |& due to race condition and signals. sigh
cat = "cat"
print "/bin/cat \"$@\"" > "cat"
print "hello" | "cat"
print close("cat")
print close("cat")
fflush()
# 11/2021: Use a nice trick to avoid race conditions in
# child processes. Thanks to Miguel Pineiro Jr. <mpj@pineiro.cc>.
#
# `%.*s' used for input pipe and output pipe
pipecmd = "eval $CMD_TO_RUN"
ENVIRON["CMD_TO_RUN"] = "echo hello"
pipecmd | getline junk
ENVIRON["CMD_TO_RUN"] = "read junk"
print "hello" | pipecmd
print close(pipecmd)
print close(pipecmd)
fflush()
# `%.*s' used for output file and output pipe"
BINMODE = 2
print "junk" > "cksum" # cksum is more portable than md5sum
print "hello" | "cksum"
print close("cksum")
print close("cksum")
fflush()
}
|
