What the meaning of $1 before the Filename

Question

function copy_nfs_files {
        [ -f /proc/self/mountstats ] && cp /proc/self/mountstats $1/proc-self-mountstats.$2 >/dev/null 2>&1
        [ -f /proc/net/rpc/nfsd ] && cp /proc/net/rpc/nfsd $1/proc-net-rpc-nfsd.$2 >/dev/null 2>&1
}

This bash function copies two files /proc/self/mountstats and /proc/net/rpc/nfsd. What is the meaning of $1/proc-self-mountstats.$2? I see $1 just before file name and $2 at the end of file?

I understand that $0 is the basename, $1 the first arg, $2 the second arg, and so on. What I want to know is what it will yield when they are using like $1/proc-self-mountstats.$2. Let's suppose $1 = 123 and $2 = 100. You mean it will become 123/proc-self-mountstats.100?

I googled around to get the meaning but did not get anything around on this.

Sure, why would you assume the semantics change? – stephanmg Nov 07 '19 at 14:46 — stephanmg, Nov 07 '19 at 14:46
It's evidently a typo for `"$1"`. – Toby Speight Nov 07 '19 at 15:52 — Toby Speight, Nov 07 '19 at 15:52

score 0 · Accepted Answer · answered Nov 07 '19 at 13:32

What I want to know is what it will yield when they are using like $1/proc-self-mountstats.$2. Let's suppose $1 = 123 and $2 = 100. You mean it will become 123/proc-self-mountstats.100?

Yes, that's right. The expanded values are joined together with the literal parts to form one big string.

score -2 · Answer 2 · edited Nov 07 '19 at 18:00

-2

Outside a function $1 stands for the first argument of your script. Inside a function $1 stands for the first argument to the function.

edited Nov 07 '19 at 18:00

stephanmg

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answered Nov 07 '19 at 12:56

icy

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Outside a function it's the script's first argument. Inside a function it's the *function's* first argument. – John Kugelman Nov 07 '19 at 13:34

What the meaning of $1 before the Filename

2 Answers2