How to pass arguments to /bin/bash?

Question

In my terminal, I do $ myprogram myfile.ext.

I want to be able to do the same via the command /bin/bash, but it is not working.

I tried

$ /bin/bash -c -l myprogram myfile.ext

but it is not working. It seems that my program is launched but without my file.ext as an option (as an input file)

Does anyone has a clue on how to do that?

Why I ask this question

I want to launch myprogram via NSTask in an a program I am writing for OSX, with the cocoa framework. If I simply ask NSTask to launch my program, it seems that some variable environment are missing. So, what I try is to launch a shell and inside this shell to launch myprogram.

Please give the full context of what you're trying to do including any environment conditions that make this a special case. Based on your comments to answers this is not just a case of invoking bash with a filename to run. — kojiro, Apr 13 '14 at 00:17

score 3 · Answer 1 · answered Apr 12 '14 at 03:04

Drop the -c altogether. From the manpage:

bash [options] [file]
…
Bash  is  an  sh-compatible command language interpreter that executes commands read from the standard input or from a file.

Thus, you can execute your program via

bash myprogram myfile.ext

and myfile.ext will be the first positional parameter.

bash -l myprogram myfile.ext

will work as well, (but whether or not bash is invoked as a login shell seems tangential to this question.)

score 1 · Answer 2 · answered Apr 12 '14 at 02:28

1

-c string 
    If  the  -c  option  is  present, then commands are read from
    string.  If there are arguments after the  string,  they  are
    assigned to the positional parameters, starting with $0.

You need to quote the command passed in as string so it's treated as a single argument for the -c option, which then gets executed normally with the argument following the command, i.e.

/bin/bash -c -l 'myprogram myfile.ext'

answered Apr 12 '14 at 02:28

Reinstate Monica Please

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Thanks!! It is working if I type this command in a terminal. But, if if try to execute it via `fork()` or `exec()`it is not working... Any idea? – Colas Apr 12 '14 at 02:46
The error I get is `/bin/bash: myprogarm myfile.ext No such file or directory` whereas `/bin/bash -c -l 'myprogram'` works. – Colas Apr 12 '14 at 02:49
@Colas Try providing the full path to `myprogarm` – Reinstate Monica Please Apr 12 '14 at 02:52
I tried too, but the result is the same. :( – Colas Apr 12 '14 at 02:59
@Colas Can you show the full `exec` or `fork` you're trying? – Reinstate Monica Please Apr 12 '14 at 02:59
I try to launch `pdflatex` via `cocoa`. It is `/bin/bash -l -c '/usr/texbin/pdflatex myfile.tex'`. I launch it via `NSTask`. – Colas Apr 12 '14 at 03:01
@Colas Haven't used `NSTask`, but are you sure you have correct quoting within it? The `bash` command looks fine, though I would provide the full path to `myfile.tex` as well depending on where it's located. – Reinstate Monica Please Apr 12 '14 at 03:05
Good idea, but even with the full path of `myfile.tex` it is nor working :( – Colas Apr 12 '14 at 03:09

How to pass arguments to /bin/bash?

Why I ask this question

2 Answers2

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