* What does " test ... || gcc ..." mean? [not found] ` <015701c17e6b$9844f120$7add18ac@amr.corp.intel.com> @ 2001-12-06 7:57 ` Luker Lu 2001-12-07 4:44 ` Andrea 'Fyre Wyzard' Bocci 0 siblings, 1 reply; 2+ messages in thread From: Luker Lu @ 2001-12-06 7:57 UTC (permalink / raw) To: gcc-help Hi all, I want to understand the source code of gcc so I am studying the build process at first. In the process of "make bootstrap", the following command appears: test x"no" != xyes || \ gcc -c -DHAVE_CONFIG_H -g -O2 -I. -I../../source/libiberty/../include ../../source/libiberty/argv.c -o pic/argv.o I know what "test" and "gcc" are, but can't understand the whole command. Could someone explain me what it does? What does this "||" between test and gcc mean? thanks in advance! Luker Lu ^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: What does " test ... || gcc ..." mean? 2001-12-06 7:57 ` What does " test ... || gcc ..." mean? Luker Lu @ 2001-12-07 4:44 ` Andrea 'Fyre Wyzard' Bocci 0 siblings, 0 replies; 2+ messages in thread From: Andrea 'Fyre Wyzard' Bocci @ 2001-12-07 4:44 UTC (permalink / raw) To: Luker Lu, gcc-help At 16.57 06/12/01 (GMT +0100), Luker Lu wrote: >Hi all, > >I want to understand the source code of gcc so I am studying the build >process at first. In the process of "make bootstrap", the following command >appears: > >test x"no" != xyes || \ > gcc -c -DHAVE_CONFIG_H -g -O2 -I. -I../../source/libiberty/../include >../../source/libiberty/argv.c -o pic/argv.o > >I know what "test" and "gcc" are, but can't understand the whole command. >Could someone explain me what it does? What does this "||" between test and >gcc mean? >thanks in advance! > >Luker Lu Here is a fast explanation: || is the OR operator. It can also be used as a flow control operator, just like an if-then-else check. That is, you can write a C style if-then-else block if (condition) true-statement else false-statement as test condition && true-statement || false-statement However, unlike the C block, the "&& true-statement part" is not necessary, and can be skipped. For more infos, have a look at sh or bahs man pages. fwyzard ^ permalink raw reply [flat|nested] 2+ messages in thread
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[not found] ` <015701c17e6b$9844f120$7add18ac@amr.corp.intel.com>
2001-12-06 7:57 ` What does " test ... || gcc ..." mean? Luker Lu
2001-12-07 4:44 ` Andrea 'Fyre Wyzard' Bocci
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